Stimulation apparatus

ABSTRACT

Provided is a medical apparatus for a patient comprising an external system and an implantable system. The external system can be configured to transmit one or more transmission signals, each transmission signal comprising at least power or data. The implantable system can be configured to receive the one or more transmission signals from the external system. The external system comprises a first external device comprising at least one external antenna configured to transmit a first transmission signal to the implantable system. The implantable system comprises a first implantable device comprising at least one implantable antenna configured to receive the first transmission signal from the first external device. At least one of the external antenna or implantable antenna comprises an antenna assembly comprising: at least one transmitting/receiving antenna; and at least one shielding element positioned between the at least one transmitting/receiving antenna and an interfering component.

CROSS REFERENCE

This application is a continuation of PCT Application No.PCT/US17/68803, filed Dec. 28, 2017; which claims priority to U.S.Provisional Patent Application Ser. No. 62/441,056, filed Dec. 30, 2016;the entire contents of which are incorporated herein by reference intheir entirety for all purposes.

DESCRIPTION OF THE INVENTION Related Applications

This application is related to: U.S. patent application Ser. No.14/975,358, titled “Method and Apparatus for Minimally InvasiveImplantable Modulators”, filed Dec. 18, 2015; U.S. patent applicationSer. No. 15/264,864, titled “Method and Apparatus for VersatileMinimally Invasive Neuromodulators”, filed Sep. 14, 2016; InternationalPCT Patent Application Serial Number PCT/US2015/036821, titled “Methodand Apparatus for Neuromodulation Treatments of Pain and OtherConditions”, filed Jun. 19, 2015; International PCT Patent ApplicationSerial Number PCT/US2016/016888, titled “Medical Apparatus Including anImplantable System and an External System”, filed Feb. 5, 2016;International PCT Patent Application Serial Number PCT/US2016/051177,titled “Apparatus for Peripheral or Spinal Stimulation”, filed Sep. 9,2016; U.S. Provisional Patent Application Ser. No. 62/341,418, titled“Methods and Systems for Insertion and Fixation of Implantable Devices”,filed May 25, 2016; U.S. Provisional Patent Application Ser. No.62/297,679, titled “Apparatus with Enhanced Stimulation Waveforms”,filed Feb. 19, 2016; U.S. Provisional Patent Application Ser. No.62/417,907, titled “Apparatus with Enhanced Stimulation Waveforms”,filed Nov. 4, 2016; U.S. Provisional Patent Application Ser. No.62/311,297, titled “Devices and Methods for Positioning External Devicesin Relation to Implanted Devices”, filed Mar. 21, 2016; and U.S.Provisional Patent Application Ser. No. 62/363,742, titled “Methods andSystems for Treating Pelvic Disorders and Pain Conditions”, filed Jul.18, 2016; the content of each of which is incorporated herein byreference in its entirety for all purposes.

FIELD OF THE INVENTION

The present invention relates generally to medical apparatus for apatient, and in particular, to stimulation apparatuses that operate withimproved efficiency and performance.

BACKGROUND OF THE INVENTION

Implantable devices that treat a patient and/or record patient data areknown. For example, implants that deliver energy such as electricalenergy, or deliver agents such as pharmaceutical agents are commerciallyavailable. Implantable electrical stimulators can be used to pace ordefibrillate the heart, as well as modulate nerve tissue (e.g., to treatpain). Most implants are relatively large devices with batteries andlong conduits, such as implantable leads configured to deliverelectrical energy or implantable tubes (i.e., catheters) to deliver anagent. These implants require a fairly invasive implantation procedure,and periodic battery replacement, which requires additional surgery. Thelarge sizes of these devices and their high costs have prevented theiruse in a variety of applications.

Nerve stimulation treatments have shown increasing promise recently,showing potential in the treatment of many chronic diseases includingdrug-resistant hypertension, motility disorders in the intestinalsystem, metabolic disorders arising from diabetes and obesity, and bothchronic and acute pain conditions among others. Many of theseimplantable device configurations have not been developed effectivelybecause of the lack of miniaturization and power efficiency, in additionto other limitations.

There is a need for apparatus, systems, devices, and methods thatprovide one or more implantable devices and are designed to provideenhanced treatment of pain and other enhanced benefits.

SUMMARY

Medical apparatus of the present inventive concepts can include antennaassemblies that include one or more antennas and one or more shieldingelements.

According to an aspect of the inventive concepts, a medical apparatusfor a patient comprises an external system and an implantable system.The external system can be configured to transmit one or moretransmission signals, each transmission signal comprising at least poweror data. The implantable system can be configured to receive the one ormore transmission signals from the external system. The external systemcomprises a first external device comprising: at least one externalantenna configured to transmit a first transmission signal to theimplantable system, the first transmission signal comprising at leastpower or data; an external transmitter configured to drive the at leastone external antenna; an external power supply configured to providepower to at least the external transmitter; and/or an externalcontroller configured to control the external transmitter. Theimplantable system comprises a first implantable device comprising: atleast one implantable antenna configured to receive the firsttransmission signal from the first external device; an implantablereceiver configured to receive the first transmission signal from the atleast one implantable antenna; at least one implantable functionalelement configured to interface with the patient; an implantablecontroller configured to control the at least one implantable functionalelement; an implantable energy storage assembly configured to providepower to an element selected from the group consisting of: the at leastone implantable functional element; the implantable controller; theimplantable receiver; and combinations thereof and/or an implantablehousing surrounding at least the implantable controller and theimplantable receiver. At least one of the external antenna orimplantable antenna comprises an antenna assembly comprising: at leastone transmitting/receiving antenna; and at least one shielding elementpositioned between the at least one transmitting/receiving antenna andan interfering component.

In some embodiments, the shielding element comprises multiple shieldingelements.

In some embodiments, the shielding element comprises a material selectedfrom the group consisting of: high permeability material; low magneticloss tangent material; low conductivity material; and combinationsthereof. The shield can comprise a magnetic permeability (u′) of greaterthan or equal to 40. The shield can comprise a magnetic loss tangent(u″/u′) of less than or equal to 0.025. The shield can comprise aconductivity of less than or equal to 1e−3 S/m. The shield can comprisea conductivity of less than or equal to 1e−5 S/m. The at least onetransmitting/receiving antenna can be configured to delivertransmissions with an operating frequency above 1 Mhz. The at least onetransmitting/receiving antenna can be configured to delivertransmissions with an operating frequency above 10 Mhz.

In some embodiments, the shielding element comprises high frequencyferrite. The at least one transmitting/receiving antenna is configuredto deliver transmissions with an operating frequency above 1 Mhz, orabove 10 Mhz, such as at an operating frequency of approximately 40.68MHz. These transmissions can be performed at a power level between 10 mWand 4 W, such as a power level between 10 mW and 400 mW.

In some embodiments, the shielding element comprises a material selectedfrom the group consisting of: electromagnetically absorptive material;RF absorptive material; conductive material; and combinations thereof.

In some embodiments, the shielding element is configured to shield theat least one transmitting/receiving antenna from interfering components.

In some embodiments, the shielding element is configured to shield atleast a portion of the environment surrounding the at least onetransmitting/receiving antenna. The shielding element can be configuredto shield the environment on the side of the shield opposite the atleast one transmitting/receiving antenna. The shielding element can beconfigured to reduce electromagnetic shielding and/or filteringrequirements of the apparatus. The shielding element can comprise amaterial selected from the group consisting of: electromagneticallyabsorptive material; RF absorptive material; conductive material; andcombinations thereof.

In some embodiments, the interfering component comprises at least oneelectrically conductive component.

In some embodiments, the interfering component comprises at least onemetallic component.

In some embodiments, the interfering component comprises at least onecomponent that would otherwise cause an effect selected from the groupconsisting of: undesired loading; undesired coupling; a parasiticeffect; and combinations thereof.

In some embodiments, the interfering component comprises at least onecomponent to which transmissions from the at least onetransmitting/receiving antenna would otherwise cause a deleteriouseffect.

In some embodiments, the apparatus further comprises at least onespace-providing element. The at least one space-providing element can bepositioned between the at least one transmitting/receiving antenna andthe shield. The at least one space-providing element can comprise a gap.The at least one space-providing element can comprise a thicknessbetween 0.01 mm and 5 mm, or a thickness between 0.25 mm and 1 mm. Theat least one space-providing element can comprise a non-conductivedielectric material. The at least one space-providing element cancomprise a material selected from the group consisting of: glassreinforced epoxy laminate; acetal; and combinations of one or more ofthese. The at least one space-providing element comprises a dielectricloss tangent of less than or equal to 0.05, less than or equal to 0.02;and/or less than or equal to 0.005. The at least one space-providingelement comprises multiple spacers. A first space-providing element canbe positioned on a first side of the at least one transmitting/receivingantenna and a second space-providing element can be positioned on asecond side of the at least one transmitting/receiving antenna.

In some embodiments, the external device comprises a first housing and aseparate second housing. The first housing can surround at least thetransmitting/receiving antenna, the second housing can surround at leastthe external transmitter, the first housing can be constructed andarranged for placement proximate the patient's skin, and the secondhousing can be constructed and arranged for placement relatively awayfrom the patient's skin.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features and advantages of embodimentsof the present inventive concepts will be apparent from the moreparticular description of preferred embodiments, as illustrated in theaccompanying drawings in which like reference characters refer to thesame or like elements. The drawings are not necessarily to scale,emphasis instead being placed upon illustrating the principles of thepreferred embodiments.

FIG. 1 is a schematic anatomical view of a medical apparatus comprisingan external system and an implantable system, consistent with thepresent inventive concepts.

FIG. 1A is a schematic view of an antenna assembly comprising an antennaand a shield, consistent with the present inventive concepts.

FIGS. 2A-2F are views of various configurations of antenna assemblies,consistent with the present inventive concepts.

FIG. 3 is a schematic anatomical view of a medical apparatus comprisingan external system including a shielded antenna assembly, consistentwith the present inventive concepts.

FIGS. 4A-4C are an assembled, sectional, perspective view, an explodedperspective view and an exploded side view of an external systemincluding a shielded antenna assembly, consistent with the presentinventive concepts.

FIG. 4D is a side, schematic view of a laminate antenna assemblycomprising multiple antenna elements on different layers of thelaminate, consistent with the present inventive concepts.

FIGS. 4E-4F are a top view and bottom view, respectively, of a laminateantenna assembly comprising multiple antenna elements and multipleconnecting vias, consistent with the present inventive concepts.

FIGS. 5A-5B are side sectional views of external devices, each includinga shielded antenna assembly, consistent with the present inventiveconcepts.

FIG. 6 is a side sectional view of an implantable device including ashielded antenna assembly, consistent with the present inventiveconcepts.

FIG. 7 is a perspective view of an antenna assembly comprising multipleantennas, consistent with the present inventive concepts.

FIG. 8 is a perspective view of an external device comprising anattached antenna assembly, consistent with the present inventiveconcepts.

DETAILED DESCRIPTION OF THE DRAWINGS

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting of the inventiveconcepts. Furthermore, embodiments of the present inventive concepts mayinclude several novel features, no single one of which is solelyresponsible for its desirable attributes or which is essential topracticing an inventive concept described herein. As used herein, thesingular forms “a,” “an” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise.

It will be further understood that the words “comprising” (and any formof comprising, such as “comprise” and “comprises”), “having” (and anyform of having, such as “have” and “has”), “including” (and any form ofincluding, such as “includes” and “include”) or “containing” (and anyform of containing, such as “contains” and “contain”) when used herein,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various limitations, elements,components, regions, layers and/or sections; these limitations,elements, components, regions, layers and/or sections should not belimited by these terms. These terms are only used to distinguish onelimitation, element, component, region, layer or section from anotherlimitation, element, component, region, layer, or section. Thus, a firstlimitation, element, component, region, layer or section discussed belowcould be termed a second limitation, element, component, region, layeror section without departing from the teachings of the presentapplication.

It will be further understood that when an element is referred to asbeing “on”, “attached”, “connected” or “coupled” to another element, itcan be directly on or above, or connected or coupled to, the otherelement, or one or more intervening elements can be present. Incontrast, when an element is referred to as being “directly on”,“directly attached”, “directly connected” or “directly coupled” toanother element, there are no intervening elements present. Other wordsused to describe the relationship between elements should be interpretedin a like fashion (e.g., “between” versus “directly between,” “adjacent”versus “directly adjacent,” etc.). A first component (e.g., a device,assembly, housing or other component) can be “attached”, “connected” or“coupled” to another component via a connecting filament (as definedbelow). In some embodiments, an assembly comprising multiple componentsconnected by one or more connecting filaments is created during amanufacturing process (e.g., pre-connected at the time of animplantation procedure of the system of the present inventive concepts).Alternatively or additionally, a connecting filament can comprise one ormore connectors (e.g., a connectorized filament comprising a connectoron one or both ends), and a similar assembly can be created by a user(e.g., a clinician) operably attaching the one or more connectors of theconnecting filament to one or more mating connectors of one or morecomponents of the assembly.

It will be further understood that when a first element is referred toas being “in”, “on”, and/or “within” a second element, the first elementcan be positioned: within an internal space of the second element,within a portion of the second element (e.g., within a wall of thesecond element); positioned on an external and/or internal surface ofthe second element; and combinations of one or more of these.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like may be used to describe an element and/or feature'srelationship to another element(s) and/or feature(s) as, for example,illustrated in the figures. It will be understood that the spatiallyrelative terms are intended to encompass different orientations of thedevice in use and/or operation in addition to the orientation depictedin the figures. For example, if the device in a figure is turned over,elements described as “below” and/or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.The device can be otherwise oriented (e.g., rotated 90 degrees or atother orientations) and the spatially relative descriptors used hereininterpreted accordingly.

As used herein, the term “proximate” shall include locations relativelyclose to, on, in and/or within a referenced component or other location.

The term “and/or” where used herein is to be taken as specificdisclosure of each of the two specified features or components with orwithout the other. For example, “A and/or B” is to be taken as specificdisclosure of each of (i) A, (ii) B and (iii) A and B, just as if eachis set out individually herein.

The term “diameter” where used herein to describe a non-circulargeometry is to be taken as the diameter of a hypothetical circleapproximating the geometry being described. For example, when describinga cross section, such as the cross section of a component, the term“diameter” shall be taken to represent the diameter of a hypotheticalcircle with the same cross sectional area as the cross section of thecomponent being described.

The terms “major axis” and “minor axis” of a component where used hereinare the length and diameter, respectively, of the smallest volumehypothetical cylinder which can completely surround the component.

The term “transducer” where used herein is to be taken to include anycomponent or combination of components that receives energy or anyinput, and produces an output. For example, a transducer can include anelectrode that receives electrical energy, and distributes theelectrical energy to tissue (e.g., based on the size of the electrode).In some configurations, a transducer converts an electrical signal intoany output, such light (e.g., a transducer comprising a light emittingdiode or light bulb), sound (e.g., a transducer comprising a piezocrystal configured to deliver ultrasound energy), pressure, heat energy,cryogenic energy, chemical energy; mechanical energy (e.g., a transducercomprising a motor or a solenoid), magnetic energy, and/or a differentelectrical signal (e.g., a Bluetooth or other wireless communicationelement). Alternatively or additionally, a transducer can convert aphysical quantity (e.g., variations in a physical quantity) into anelectrical signal. A transducer can include any component that deliversenergy and/or an agent to tissue, such as a transducer configured todeliver one or more of: electrical energy to tissue (e.g., a transducercomprising one or more electrodes); light energy to tissue (e.g., atransducer comprising a laser, light emitting diode and/or opticalcomponent such as a lens or prism); mechanical energy to tissue (e.g., atransducer comprising a tissue manipulating element); sound energy totissue (e.g., a transducer comprising a piezo crystal); thermal energyto tissue (e.g., heat energy and/or cryogenic energy); chemical energy;electromagnetic energy; magnetic energy; and combinations of one or moreof these.

The term “transmission signal” where used herein is to be taken toinclude any signal transmitted between two components, such as via awired or wireless communication pathway. For example, a transmissionsignal can comprise a power and/or data signal wirelessly transmittedbetween a component external to the patient and one or more componentsimplanted in the patient. A transmission signal can include one or moresignals transmitted using body conduction. Alternatively oradditionally, a transmission signal can comprise reflected energy, suchas energy reflected from any power and/or data signal. A transmissionsignal can comprise a modulated signal (e.g., a frequency modulatedsignal) which includes a carrier frequency (also referred to as an“operating frequency” herein).

The term “data signal” where used herein is to be taken to include atransmission signal including at least data. For example, a data signalcan comprise a transmission signal including data and sent from acomponent external to the patient and one or more components implantedin the patient. Alternatively, a data signal can comprise a transmissionsignal including data sent from an implanted component to one or morecomponents external to the patient. A data signal can comprise aradiofrequency signal including data (e.g., a radiofrequency signalincluding both power and data) and/or a data signal sent using bodyconduction.

The term “implantable” where used herein is to be taken to define acomponent which is constructed and arranged to be fully or partiallyimplanted in a patient's body and/or a component that has been fully orpartially implanted in a patient. The term “external” where used hereinis to be taken to define a component which is constructed and arrangedto be positioned outside of the patient's body.

The terms “connection”, “connected”, “connecting” and the like, whereused herein, are to be taken to include any type of connection betweentwo or more components. The connection can include an operableconnection which allows multiple connected components to operatetogether such as to transfer information, power and/or material (e.g.,an agent to be delivered) between the components. An operable connectioncan include a physical connection, such as a physical connectionincluding one or more wires, optical fibers, wave guides, tubes such asfluid transport tubes and/or linkages such as translatable rods or othermechanical linkages. Alternatively or additionally, an operableconnection can include a non-physical or “wireless” connection, such asa wireless connection in which information and/or power is transmittedbetween components using electromagnetic energy. A connection caninclude a connection selected from the group consisting of: a wiredconnection; a wireless connection; an electrical connection; amechanical connection; an optical connection; a sound propagatingconnection; a fluid connection; and combinations of one or more ofthese.

The term “connecting filament” where used herein is to be taken todefine a filament connecting a first component to a second component.The connecting filament can include a connector on one or both ends,such as to allow a user to operably attach at least one end of thefilament to a component. A connecting filament can comprise one or moreelements selected from the group consisting of: wires; optical fibers;fluid transport tubes; mechanical linkages; wave guides; flexiblecircuits; and combinations of one or more of these. A connectingfilament can comprise rigid filament, a flexible filament or it cancomprise one or more flexible portions and one or more rigid portions.

The term “connectorized” where used herein is to be taken to refer to afilament, housing or other component that includes one or moreconnectors (e.g., clinician or other user-attachable connectors) foroperably connecting that component to a mating connector (e.g., of thesame or different component).

The terms “stimulation parameter”, “stimulation signal parameter” or“stimulation waveform parameter” where used herein can be taken to referto one or more parameters of a stimulation waveform (also referred to asstimulation signal). Applicable stimulation parameters of the presentinventive concepts shall include but are not limited to: amplitude(e.g., amplitude of voltage and/or current); average amplitude; peakamplitude; frequency; average frequency; period; phase; polarity; pulseshape; a duty cycle parameter (e.g., frequency, pulse width and/or offtime); inter-pulse gap; polarity; burst-on period; burst-off period;inter-burst period; pulse train; train-on period; train-off period;inter-train period; drive impedance; duration of pulse and/or amplitudelevel; duration of stimulation waveform; repetition of stimulationwaveform; an amplitude modulation parameter; a frequency modulationparameter; a burst parameter; a power spectral density parameter; ananode/cathode configuration parameter; amount of energy and/or power tobe delivered; rate of energy and/or power delivery; time of energydelivery initiation; method of charge recovery; and combinations of oneor more of these. A stimulation parameter can refer to a singlestimulation pulse, multiple stimulation pulses, or a portion of astimulation pulse. The term “amplitude” where used herein can refer toan instantaneous or continuous amplitude of one or more stimulationpulses (e.g., the instantaneous voltage level or current level of apulse). The term “pulse” where used herein can refer to a period of timeduring which stimulation energy is relatively continuously beingdelivered. In some embodiments, stimulation energy delivered during apulse comprises energy selected from the group consisting of: electricalenergy; magnetic energy; electromagnetic energy; light energy; soundenergy such as ultrasound energy; mechanical energy such as vibrationalenergy; thermal energy such as heat energy or cryogenic energy; chemicalenergy; and combinations of one or more of these. In some embodiments,stimulation energy comprises electrical energy and a pulse comprises aphase change in current and/or voltage. In these embodiments, aninter-phase gap can be present within a single pulse. The term“quiescent period” where used herein can refer to a period of timeduring which zero energy or minimal energy is delivered (e.g.,insufficient energy to elicit an action potential and/or other neuronalresponse). The term “inter-pulse gap” where used herein can refer to aquiescent period between the end of one pulse to the onset of the next(sequential) pulse. The terms “pulse train” or “train” where used hereincan refer to a series of pulses. The terms “burst”, “burst of pulses” or“burst stimulation” where used herein can refer to a series of pulsetrains, each separated by a quiescent period. The term “train-on period”where used herein can refer to a period of time from the beginning ofthe first pulse to the end of the last pulse of a single train. The term“train-off period” where used herein can refer to a quiescent periodbetween the end of one train and the beginning of the next train. Theterm “burst-on period” where used herein can refer to a period of timefrom the beginning of the first pulse of the first train to the end ofthe last pulse of the last train of a single burst. The term “burst-offperiod” where used herein can refer to a quiescent period between theend of one burst and the beginning of the next burst. The term“inter-train period” where used herein can refer to a quiescent periodbetween the end of one train and the beginning of the next train. Theterm “inter-burst period” where used herein can refer to a quiescentperiod between the end of one burst and the beginning of the next burst.The term “train envelope” where used herein can refer to a curveoutlining the amplitude extremes of a series of pulses in a train. Theterm “burst envelope” where used herein can refer to a curve outliningthe amplitude extremes of a series of pulses in a burst. The term “trainramp duration” where used herein can refer to the time from the onset ofa train until its train envelope reaches a desired target magnitude. Theterm “burst ramp duration” where used herein can refer to the time fromthe onset of a burst until its burst envelope reaches a desired targetmagnitude.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable sub-combination. For example, it will be appreciated thatall features set out in any of the claims (whether independent ordependent) can be combined in any given way.

The present inventive concepts include a medical apparatus and clinicalmethods for treating a patient, such as to treat pain. The patient canbe a human or other mammalian patient. The medical apparatus cancomprise a stimulation apparatus. The medical apparatus can comprise animplantable system and an external system. The implantable system cancomprise one or more similar and/or dissimilar implantable devices. Eachimplantable device can comprise one or more implantable antennasconfigured to receive power and/or data. Each implantable device cancomprise an implantable receiver configured to receive the power and/ordata from the one or more implantable antennas. Each implantable devicecan comprise one or more implantable functional elements. An implantablefunctional element can be configured to interface with the patient(e.g., interface with tissue of the patient or interface with anypatient location). Alternatively or additionally, an implantablefunctional element can interface with a portion of an implantable device(e.g., to measure an implantable device parameter). In some embodiments,the one or more implantable functional elements can comprise one or moretransducers, electrodes, and/or other elements configured to deliverenergy to tissue. Alternatively or additionally, the one or moreimplantable functional elements can comprise one or more sensors, suchas a sensor configured to record a physiologic parameter of the patient.In some embodiments, one or more implantable functional elements areconfigured to record device information and/or patient information(e.g., patient physiologic or patient environment information).

Each implantable device can comprise an implantable controllerconfigured to control (e.g., modulate power to, send a signal to and/orreceive a signal from) the one or more implantable functional elements.In some embodiments, an implantable controller of a first implantabledevice is configured to control one or more other implantable devices.Each implantable device can comprise an implantable energy storageassembly configured to provide power to the implantable controller(e.g., a controller comprising a stimulation waveform generator), theimplantable receiver and/or the one or more implantable functionalelements. In some embodiments, an implantable energy storage assembly isfurther configured to provide power to an assembly that transmitssignals via the implantable antenna (e.g., when the implantable deviceis further configured to transmit data to one or more external devices).Each implantable device can comprise an implantable housing surroundingthe implantable controller and the implantable receiver. In someembodiments, one or more implantable antennas are positioned within theimplantable housing. Alternatively or additionally, one or moreimplantable antennas and/or implantable functional elements can betethered (e.g., electrically tethered) to the implantable housing. Insome embodiments, one or more implantable functional elements arepositioned on an implantable lead, such as a flexible lead mechanicallyfixed or attachable to the implantable housing and operably connected(e.g., electrically, fluidly, optically, and/or mechanically) to one ormore components internal to the implantable housing. The implantablelead can be inserted (e.g., tunneled) through tissue of the patient,such that its one or more functional elements are positioned proximatetissue to be treated and/or positioned at an area in which data is to berecorded.

The external system of the medical apparatus of the present inventiveconcepts can comprise one or more similar and/or dissimilar externaldevices. Each external device can comprise one or more external antennasconfigured to transmit power and/or data to one or more implantedcomponents of the implantable system. Each external device can comprisean external transmitter configured to drive the one or more externalantennas. Each external device can comprise an external power supplyconfigured to provide power to at least the external transmitter. Eachexternal device can comprise an external programmer configured tocontrol the external transmitter and/or an implantable device (e.g.,when an external power transmitter is not included in the apparatus orotherwise not present during use). Each external device can comprise anexternal housing that surrounds at least the external transmitter. Insome embodiments, the external housing surrounds the one or moreexternal antennas, the external power supply and/or the externalprogrammer.

The external programmer can comprise a discrete controller separate fromthe one or more external devices, and/or a controller integrated intoone or more external devices. The external programmer can comprise auser interface, such as a user interface configured to set and/or modifyone or more treatment and/or data recording settings of the medicalapparatus of the present inventive concepts. In some embodiments, theexternal programmer can be configured to collect and/or diagnoserecorded patient information, such as to provide the information and/ordiagnosis to a clinician of the patient, to a patient family memberand/or to the patient themselves. The collected information and/ordiagnosis can be used to adjust treatment or other operating parametersof the medical apparatus.

In some embodiments, a medical apparatus comprises a stimulationapparatus for activating, blocking, affecting or otherwise stimulating(hereinafter “stimulate” or “stimulating”) tissue of a patient, such asnerve tissue or nerve root tissue (hereinafter “nerve”, “nerves”, “nervetissue”, or “nervous system tissue”). The stimulation apparatuscomprises an external system configured to transmit power, and animplanted system configured to receive the power from the externalsystem and to deliver stimulation energy to tissue. The deliveredstimulation energy can comprise one or more stimulation waveforms, suchas a stimulation waveform configured to enhance treatment of pain whileminimizing undesired effects. The stimulation signal (also referred toas “stimulation energy”) delivered by the implanted system can beindependent of the power received from the external system, such as tobe independent of one or more of: the position of one or more componentsof the external system; the changing position of one or more componentsof the external system; the frequency of the power received from theexternal system; the amplitude of the power received from the externalsystem; changes in amplitude of the power received from the externalsystem; duty cycle of the power received from the external system;envelope of the power received from the external system; andcombinations of one or more of these.

Referring now to FIG. 1, a schematic anatomical view of a medicalapparatus for treating and/or diagnosing a patient is illustrated,consistent with the present inventive concepts. Apparatus 10 comprisesimplantable system 20 and external system 50. Implantable system 20comprises implantable device 200 shown implanted beneath the skin ofpatient P. In some embodiments, implantable system 20 comprises multipleimplantable devices 200 (singly or collectively implantable device 200),such as is described in applicant's application International PCT PatentSerial Number PCT/US2016/051177, titled “Apparatus for Peripheral orSpinal Stimulation”, filed Sep. 9, 2016, the content of which isincorporated herein in its entirety for all purposes. In someembodiments, implantable system 20 comprises at least two implantabledevices, such as implantable device 200 and implantable device 200′shown in FIG. 1. Implantable device 200′ can be of similar constructionand arrangement to implantable device 200, and it can include componentsof different configuration.

External system 50 can comprise an external device 500, which includeshousing 510. In some embodiments, external system 50 comprises multipleexternal devices 500 (singly or collectively external device 500), alsoas is described in applicant's application International PCT PatentSerial Number PCT/US2016/051177, titled “Apparatus for Peripheral orSpinal Stimulation”, filed Sep. 9, 2016. In some embodiments, externalsystem 50 comprises at least two external devices (e.g., at least twoexternal devices configured to deliver power and/or data to one or moreimplantable devices 200), such as external device 500 and externaldevice 500′ shown in FIG. 1. External device 500′ can be of similarconstruction and arrangement to external device 500, and it can includecomponents of different configuration.

External system 50 can comprise external programmer 550, which cancomprise a user interface, such as user interface 555. Externalprogrammer 550 can be configured to control one or more external devices500. Alternatively or additionally, external programmer 550 can beconfigured to control one or more implantable devices 200 (e.g., when noexternal device 500 is included in apparatus 10 or otherwise no externaldevice 500 is available to communicate with an implantable device 200.

Apparatus 10 can be configured as a patient treatment apparatus, such asa stimulation apparatus configured to stimulate tissue (e.g., stimulatenerve tissue such as tissue of the central nervous system or tissue ofthe peripheral nervous system, such as to neuromodulate nerve tissue),such as by having one or more implantable devices 200 deliver and/orprovide energy (hereinafter “deliver energy”) and/or deliver an agent(e.g., a pharmaceutical compound or other agent) to one or more tissuelocations. In some embodiments, one or more implantable devices 200deliver energy and/or an agent while receiving power and/or data fromone or more external devices 500. In some embodiments, one or moreimplantable devices 200 deliver energy and/or an agent (e.g.,continuously or intermittently) using an internal power source (e.g., abattery and/or capacitor) without receiving externally supplied power,such as for periods of at least 1 hour, at least 1 day, at least 1 monthor at least 1 year. In some embodiments, one or more stimulationparameters are varied (e.g., systematically and/or randomly as describedherein), during that period.

Alternatively or additionally, apparatus 10 can be configured as apatient diagnostic apparatus, such as by having one or more implantabledevices 200 record a patient parameter (e.g., a patient physiologicparameter) from one or more tissue locations, such as while receivingpower and/or data from one or more external devices 500. In someembodiments, during its use, one or more implantable devices 200 atleast receives power from one or more external devices 500 (e.g.,without also receiving data).

Alternatively or additionally, apparatus 10 can be configured as apatient information recording apparatus, such as by having one or moreimplantable devices 200 and/or one or more external devices 500 recordpatient information (e.g., patient physiologic information and/orpatient environment information). In some embodiments, one or moreimplantable devices 200 and/or one or more external devices 500 furthercollect information (e.g., status information or configuration settings)of one or more of the components of apparatus 10.

In some embodiments, apparatus 10 is configured to deliver stimulationenergy to tissue, such as to treat pain. In particular, apparatus 10 canbe configured to deliver stimulation energy to tissue of the spinal cordand/or tissue associated with the spinal cord (“tissue of the spinalcord”, “spinal cord tissue” or “spinal cord” herein), the tissueincluding roots, ganglia, and/or other nerve tissue. The deliveredenergy can comprise energy selected from the group consisting of:electrical energy; magnetic energy; electromagnetic energy; light energysuch as infrared light energy. visible light energy and/or ultravioletlight energy; mechanical energy; thermal energy such as heat energyand/or cryogenic energy; sound energy such as ultrasonic sound energy(e.g., high intensity focused ultrasound and/or low intensity focusedultrasound) and/or subsonic sound energy; chemical energy; andcombinations of one or more of these. In some embodiments, apparatus 10is configured to deliver to tissue energy in a form selected from thegroup consisting of: electrical energy such as by providing a controlled(e.g., constant or otherwise controlled) electrical current and/orvoltage to tissue; magnetic energy (e.g., magnetic field energy) such asby applying controlled current or voltage to a coil or other magneticfield generating element positioned proximate tissue; and/orelectromagnetic energy such as by providing both current to tissue and amagnetic field to tissue. The coil or other magnetic field generatingelement can surround (e.g., at least partially surround) the targetnerve and/or it can be incorporated as part of an anchoring system tothe target tissue. Alternatively, or additionally, the magnetic energycan be applied externally and focused to specific target tissue via animplant comprising a coil and/or ferromagnetic materials. In someembodiments, the magnetic energy is configured to induce the applicationof mechanical energy. Delivered energy can be supplied in one or morestimulation waveforms, each waveform comprising one or more pulses ofenergy, as described in detail herebelow.

In some embodiments, apparatus 10 is configured as a stimulationapparatus in which external system 50 transmits a power signal toimplantable system 20, and implantable system 20 delivers stimulationenergy to tissue with a stimulation signal (also referred to as astimulation waveform), with the power signal and the stimulation signalhaving one or more different characteristics. The power signal canfurther be modulated with data (e.g., configuration or other data to besent to one or more implantable devices 200). In these embodiments, thecharacteristics of the stimulation signal delivered (e.g., amplitude,frequency, duty cycle and/or pulse width), can be independent (e.g.,partially or completely independent) of the characteristics of the powersignal transmission (e.g., amplitude, frequency, phase, envelope, dutycycle, and/or modulation). For example, the frequency and modulation ofthe power signal can change without affecting the stimulation signal, orthe stimulation signal can be changed (e.g., via external programmer550), without requiring the power signal to change. In some embodiments,implantable system 20 can be configured to rectify the power signal, andproduce a stimulation waveform with entirely difference characteristics(e.g., amplitude, frequency and/or duty cycle) from the rectified powersignal. Implantable system 20 can comprise an oscillator and/orcontroller configured to produce the stimulation signal. In someembodiments, implantable system 20 is configured to perform frequencymultiplication, in which multiple signals are multiplexed, mixed, added,and/or combined in other ways to produce a broadband stimulation signal.

In some embodiments, apparatus 10 is configured such that externalsystem 50 transmits data (e.g., data and power) to implantable system20, and implantable system 20 recovers (e.g., decodes, demodulates orotherwise recovers) the transmitted data without synchronizing to thecarrier and/or data symbol rate of the transmitted signal from externalsystem 50. In some embodiments, the transmitted signal comprises a powersignal, and a clock and/or data is recovered without synchronizing tothe power signal. In some embodiments, the transmitted signal comprisesa clock and/or data signal, and a clock and/or data is recovered withoutsynchronizing to the transmitted clock and/or data signal. In someembodiments, the recovered signal comprises a clock and/or data and aclock and/or data is recovered from the transmission signal withoutsynchronizing to the recovered clock and/or data. Avoidingsynchronization reduces power consumption of each implantable device200, such as by obviating the need for (and avoiding the power consumedby) a frequency locked loop (FLL), phase locked loop (PLL); highfrequency clock; and/or crystal oscillator needed to perform thesynchronization. Avoiding these components can also be correlated toreduced package size of each implantable device 200 (e.g., avoidance ofa relatively large sized crystal oscillator). Asynchronous data transferbetween external system 50 and implantable system 20 is alsoadvantageous as it relates to: increased communication data rate; powertransfer efficiency; operation with more than one implantable device200; and combinations of one or more of these. In some embodiments, oneor more components of apparatus 10 are of similar construction andarrangement as similar components described in U.S. patent applicationSer. No. 13/591,188, titled “Method of Making and Using an Apparatus fora Locomotive Micro-Implant using Active Electromagnetic Propulsion”,filed Aug. 21, 2012, the content of which is incorporated herein byreference in its entirety for all purposes. In some embodiments,external system 50 and implantable system 20 provide asynchronous datatransfer or are otherwise configured as described in U.S. patentapplication Ser. No. 13/734,772, titled “Method and Apparatus forEfficient Communication with Implantable Devices”, filed Jan. 4, 2013,the content of which is incorporated herein by reference in its entiretyfor all purposes.

Apparatus 10 can be configured to treat a patient disease or disorderand/or it can be configured to record patient information. Apparatus 10can be configured to treat pain, such as back pain treated bystimulating dorsal root ganglia and/or other nerves or locations of thespinal cord or other nervous system locations. In some embodiments,apparatus 10 is configured to treat a type of pain selected from thegroup consisting of: back pain; joint pain; neuropathic pain; tenniselbow; muscle pain; shoulder pain; chronic, intractable pain of the backand/or lower limbs including unilateral or bilateral pain; neuropathicgroin pain; perineal pain; phantom limb pain; complex regional painsyndrome; failed back surgery syndrome; cluster headaches; migraines;inflammatory pain; arthritis; abdominal pain; pelvic pain; andcombinations of one or more of these. In some embodiments, apparatus 10is configured to treat a patient disease or disorder selected from thegroup consisting of: chronic pain; acute pain; migraine; clusterheadaches; urge incontinence; overactive bladder; fecal incontinence;bowel disorders; tremor; obsessive compulsive disorder; depression;epilepsy; inflammation; tinnitus; high blood pressure; heart failure;carpal tunnel syndrome; sleep apnea; obstructive sleep apnea; dystonia;interstitial cystitis; gastroparesis; obesity; mobility issues;arrhythmia; rheumatoid arthritis; dementia; Alzheimer's disease; eatingdisorder; addiction; traumatic brain injury; chronic angina; congestiveheart failure; muscle atrophy; inadequate bone growth; post-laminectomypain; liver disease; Crohn's disease; irritable bowel syndrome; erectiledysfunction; kidney disease; and combinations of one or more of these.

Apparatus 10 can be configured to treat heart disease, such as heartfailure of a patient. In these embodiments, stimulation of the spinalcord can be performed. In canine and porcine animals with failinghearts, spinal cord stimulation has been shown to reverse leftventricular dilation and improve cardiac function, while suppressing theprevalence of cardiac arrhythmias. In canines, coronary artery occlusionhas been associated with increased intracardiac nerve firing, andstimulation at spinal segment T1 has been shown to suppress that nervefiring. Stimulation via apparatus 10 at one or more spinal cordlocations can be used to suppress undesired cardiac nerve firing inhumans and other mammalian patients. In some embodiments, stimulationvia apparatus 10 at multiple spinal cord locations is used to enhance acardiac treatment. For example, one or more functional elements 260 ofone or more implantable devices 200 can be implanted at one or morespinal cord locations. Power and/or data can be transmitted to the oneor more implantable devices 200 via one or more external devices 500 ofexternal system 50. One or more stimulation signals can be delivered tospinal cord tissue, such as to treat heart failure or other cardiacdisease or disorder. In some embodiments, one or more functionalelements 260 are configured to deliver energy (e.g., electrical energy)to tissue to treat heart failure, such as tissue selected from the groupconsisting of: spinal canal; nerves in the spinal canal; nerves in theepidural space; peripheral nerves; posterior spinal nerve root; dorsalroot; dorsal root ganglion; pre-ganglionic tissue on posterior spinalnerve root; post-ganglionic tissue on posterior nerve root; dorsalramus; grey ramus communicans; white ramus communicans; ventral ramus;and combinations of one or more of these. In some embodiments, one ormore functional elements of apparatus 10 (e.g., one or more functionalelements 260 of implantable system 20) are used to record a patientparameter, such as a patient heart or spine parameter, and theinformation recorded is used to adjust the delivered stimulationsignals. The at least one heart parameter can comprise a parameterselected from the group consisting of: EKG; blood oxygen; bloodpressure; heart rate; ejection fraction; wedge pressure; cardiac output;and combinations of one or more of these.

Apparatus 10 can be configured to pace and/or defibrillate the heart ofa patient. One or more functional elements 260 can be positionedproximate cardiac tissue and deliver a stimulation signal as describedherein (e.g., based on power and/or data received by implantable system20 from external system 50). The stimulation signal can be used to pace,defibrillate and/or otherwise stimulate the heart. Alternatively oradditionally, apparatus 10 can be configured to record cardiac activity(e.g., by recording EKG, blood oxygen, blood pressure, heart rate,ejection fraction, wedge pressure, cardiac output, lung impedance and/orother properties or functions of the cardiovascular system), such as todetermine an onset of cardiac activity dysfunction or other undesiredcardiac state. In some embodiments, apparatus 10 is configured to bothrecord cardiac or other information and deliver a stimulation signal tocardiac tissue (e.g., stimulation varied or otherwise based on therecorded information). For example, apparatus 10 can be configured suchthat external system 50 transmits power and/or data to implantablesystem 20. Implantable system 20 monitors cardiac activity, and upondetection of an undesired cardiovascular state, implantable system 20delivers a pacing and/or defibrillation signal to the tissue that isadjacent to one or more functional elements 260 configured to deliver acardiac stimulation signal.

Apparatus 10 can be configured to perform a diagnostic procedureincluding measuring one or more patient parameters (e.g., patientphysiologic or other patient parameters), such as are described indetail herebelow. In some embodiments, apparatus 10 is configured tomeasure a physiologic parameter that can be sensed from one or moresensor-based functional elements 260 positioned in subcutaneous tissue.In these embodiments, external system 50 can comprise an external device500 configured for placement proximate an implantable device 200implanted in a position to record data from subcutaneous tissue (e.g.,blood glucose data). The external device 500 can comprise a wrist band,a wrist watch or an arm band configuration such as when the implantabledevice 200 is positioned in subcutaneous tissue proximate the patient'swrist or upper arm. The external device 500 can comprise a leg, knee orankle band configuration, such as when one or more implantable devices200 are positioned in subcutaneous tissue proximate the patient's ankle,knee or thigh. In some embodiments, external device 500 comprises a bandor other attachment device for positioning about the thorax, neck, groinor head. Power and/or data can be sent to the implantable device 200from the external device 500, and data (e.g., blood glucose data) can besent to external device 500 (or another component of external system 50)by implantable device 200, such as using a communication configurationdescribed in detail herebelow. In some embodiments, external device 500comprises a functional element 560 configured to deliver an agent (e.g.,insulin or glucose delivered by a needle-based functional element 560),based on the information received from implantable device 200.Alternatively, or additionally, implantable device 200 comprises afunctional element 260 configured to deliver an agent (e.g., insulin orglucose delivered by a needle-based functional element 260), based onthe information recorded by implantable device 200. Various closed loopsensing and agent delivery combinations and configurations should beconsidered within the spirit and scope of the present inventiveconcepts, including but not limited to: sensing a blood parameter suchas white blood cell count and delivering a chemotherapeutic or otheragent based on the blood parameter; sensing a hormone level anddelivering a hormone or a hormone affecting agent; sensing bloodpressure and delivering stimulation energy and/or a blood pressureaffecting agent; sensing neural activity and delivering stimulationenergy and/or a neural affecting agent or other agent based on theneural activity, such as for treating epilepsy; and combinations of oneor more of these.

External system 50 can be configured to transmit power and/or data(e.g., implantable system 20 configuration data) to one or moreimplantable devices 200 of implantable system 20. Configuration dataprovided by external system 50 (e.g., via one or more antennas 540 ofone or more external devices 500) can include when to initiatestimulation delivery (e.g., energy delivery), when to stop stimulationdelivery, and/or data related to the value or change to a value of oneor more stimulation variables as described hereabove. The configurationdata can include a stimulation parameter such as an agent (e.g., apharmaceutical agent) delivery stimulation parameter selected from thegroup consisting of: initiation of agent delivery; cessation of agentdelivery; amount of agent to be delivered; volume of agent to bedelivered; rate of agent delivery; duration of agent delivery; time ofagent delivery initiation; and combinations of one or more of these. Theconfiguration data can include a sensing parameter, such as a sensingparameter selected from the group consisting of: initiation of sensorrecording; cessation of sensor recording; frequency of sensor recording;resolution of sensor recording; thresholds of sensor recording; samplingfrequency of sensor recording; dynamic range of sensor recording;initiation of calibration of sensor recording; and combinations of oneor more of these.

External system 50 can comprise one or more external devices 500.External system 50 can comprise one or more antennas 540, such as when asingle external device 500 comprises one or more antennas 540 or whenmultiple external devices 500 each comprise one or more antennas 540. Insome embodiments, antenna 540 comprises an antenna assembly, such assuch as a shielded or other antenna assembly, such as any antennaassembly 1040 described herein. The one or more antennas 540 cantransmit power and/or data to one or more antennas 240 of implantablesystem 20, such as when a single implantable device 200 comprises one ormore antennas 240 or when multiple implantable devices 200 each compriseone or more antennas 240. In some embodiments, one or more antennas 540define a radiation footprint (e.g., a footprint defining a volume, suchas a volume of tissue, in which electromagnetic transmissions radiatedby antennas 540 can be properly received by antennas 240), such as isdescribed in applicant's International PCT Patent Application SerialNumber PCT/US2016/016888, titled “Medical Apparatus including anImplantable System and an External System”, filed Feb. 5, 2016; thecontent of which is incorporated herein by reference in its entirety forall purposes.

External system 50 transmits power and/or data with a transmissionsignal comprising at least one wavelength, λ. External system 50 and/orimplantable system 20 can be configured such that the distance betweenan external antenna 540 transmitting the power and/or data and one ormore implantable antennas 240 receiving the power and/or datatransmission signal is equal to between 0.1λ, and 10.0λ, such as between0.2λ, and 2.0λ. In some embodiments, one or more transmission signalsare delivered at a frequency range between 10 MHz and 100 MHz, such asapproximately 40.68 MHz. In some embodiments, one or more transmissionsignals are delivered at a power level between 10 mW and 4 W, such as apower level between 10 mW and 400 mW. In some embodiments, one or moretransmission signals are delivered at a frequency range between 0.1 GHzand 10.6 GHz, such as between 0.1 GHz and 3.0 GHz, between 0.4 GHz and1.5 GHz, or between 0.902 GHz and 0.928 GHz, or in a frequency rangeproximate to 866 MHz, or approximately between 863 MHz and 870 MHz.

In addition to transmitting power and/or data to implantable system 20,external system 50 can be further configured to provide information(e.g., patient information and/or apparatus 10 performance information)to one or more other devices, such as tool 60 shown in FIG. 1 anddescribed in detail herebelow.

One or more external devices 500 (singly or collectively external device500) can be configured to transmit power and/or data (e.g., implantablesystem 20 configuration data) to one or more implantable devices 200. Insome embodiments, one or more external devices 500 are configured totransmit both power and data (e.g., simultaneously and/or sequentially)to one or more implantable devices 200. In some embodiments, one or moreexternal devices 500 are further configured to receive data from one ormore implantable devices 200 (e.g., via data transmitted by one or moreantennas 240 of one or more implantable devices 200). Each externaldevice 500 can comprise housing 510, power supply 570, a transmitter530, and/or one or more antennas 540, each described in detailherebelow. Each external device 500 can further comprise one or morefunctional elements 560, such as a functional element comprising asensor, electrode, energy delivery element, a magnetic-field generatingtransducer, and/or any transducer, also described in detail herebelow.In some embodiments, a functional element 560 comprises one or moresensors configured to monitor performance of external device 500 (e.g.,to monitor voltage of power supply 570, quality of transmission of powerand/or data to implantable system 20, temperature of a portion of anexternal device 500, and the like).

One or more housings 510 (singly or collectively housing 510) of eachexternal device 500 can comprise one or more rigid and/or flexiblematerials which surround various components of external device 500 suchas antenna 540, transmitter 530 and/or power supply 570 shown in FIG. 1.In some embodiments, a single external device 500 comprises multiplediscrete (i.e., separate) housings 510, two or more of which cantransfer data or other signals via a wired or wireless connection. Insome embodiments, a housing 510 further surrounds an external programmer550 and/or a power supply 570. In some embodiments, housing 510comprises both a rigid material and a flexible material. In someembodiments, housing 510 comprises a material selected from the groupconsisting of: plastic; injection-molded plastic; an elastomer; metal;and combinations of one or more of these. In some embodiments, housing510 comprises a shielded portion (e.g., shielded to prevent transmissionof electromagnetic waves), and an unshielded portion, such as anunshielded portion surrounding antenna 540.

Housing 510 can comprise an adhesive element, such as an adhesiveelement configured to temporarily attach an external device 500 to thepatient's skin. Housing 510 can be constructed and arranged to engage(e.g., fit in the pocket of) a patient attachment device, such aspatient attachment device 70 described herebelow.

One or more antennas 540 (singly or collectively antenna 540) can eachcomprise one or more external antennas. Antenna 540 can comprise one ormore polarizable antennas, such as one or more antennas with adjustablepolarization. Antenna 540 can comprise an array of antennas, such as anarray of antennas configured to: support beam shaping and/or focusing;allow adjustment of the amplitude and/or phase of the transmissionsignal; increase the radiation footprint; and combinations of one ormore of these. An array of antennas 540 can be configured to beselectively activated, such as to improve coupling with one or moreimplanted antennas 240, such as to adjust for movement of the array ofthe antennas 540 relative to the implanted antennas 240. Antenna 540 cancomprise an array of selectable conductors configured to adjust aradiation pattern and/or an electromagnetic field of a resultantantenna. Antenna 540 can comprise a surface and shield materialpositioned on the surface, such as when the shield material ispositioned on the side facing away from the patient's skin. The shieldmaterial can comprise radio-absorptive shield material and/orradio-reflective shield material. One or more antennas 540 can bepositioned in a housing 510 that is otherwise void of other components(e.g., void of power supply 570 and transmitter 530), such as when anantenna 540 is positioned within a first housing 510 and communicateswith components positioned in a second housing 510.

In some embodiments, a spacing element, spacer 591 is positioned betweenantenna 540 and the patient's skin, such as a spacer comprising athickened portion of housing 510 or a discrete spacer 591 placed on aside of housing 510 (as shown) or on a side of antenna 540. Spacer 591can comprise one or more materials that match the impedance of antenna540 to the impedance of the patient's tissue. Spacer 591 can comprise athickness of between 0.1 cm to 3 cm, such as a thickness between 0.2 cmand 1.5 cm. Spacer 591 can comprise materials which isolate heat (e.g.,a spacer 591 comprising thermally insulating material). Alternatively,or additionally, housing 510 can comprise a heat insulating and/ordissipating material. Spacer 591 can comprise a soft or otherwisecompressible material (e.g., foam) for patient comfort. Spacer 591 canbe inflatable, such as to control the separation distance of an externalantenna 540 from the patient's skin. An inflatable spacer 591 can becompartmentalized into several sections with independently controlledair pressure or volume to adjust the separation distance of an externalantenna 540 and the patient's skin and/or its angle (e.g., tilt) withrespect to the tissue surface.

In some embodiments, antenna 540 comprises a multi-feed point antenna,such as a multi-feed point antenna configured to: support beam shapingand/or focusing; allow adjustment of amplitude and/or phase of atransmission signal; increase the radiation footprint; or combinationsof one or more of these.

In some embodiments, antenna 540 comprises one or more antennas selectedfrom the group consisting of: patch antenna; slot antenna; array ofantennas; a loop antenna (e.g., a concentric loop antenna); antennaloaded with reactive elements; dipole antenna; quadrupole antenna;multi-pole antenna; polarizable antenna; selectable conductors that forman antenna; and combinations of one or more of these.

Antenna 540 can comprise a major axis between 1 cm and 10 cm, such as amajor axis between 2 cm and 5 cm. Antenna 540 can be further configuredto receive a signal, such as when an antenna 240 is configured totransmit data to an external device 500. Antenna 540 can be positionedon (e.g., fabricated onto) a substrate, such as a flexible printedcircuit board or other printed circuit board (e.g., a single or multiplelayer printed circuit board comprising electrical traces connectingcomponents).

A single external antenna 540 can be configured to transmit power and/ordata to multiple implantable devices 200 (e.g., each containing one ormore antennas 240). In some embodiments, a single external device 500,comprising one or more antennas 540 can be configured to transmit powerand/or data to multiple implantable devices 200.

One or more antennas 540 can comprise a multi-turn spiral loop antenna,such as a multi-turn spiral loop antenna configured to desensitizecoupling sensitivity and/or boost input voltage. In some embodiments,one or more antennas 540 comprise multiple concentric loops with varieddimensions, such as concentric loops configured to desensitize couplingsensitivity. In these embodiments, the multiple concentric loops can be:connected in parallel and driven from the same feed point; driven fromthe same feed point and connected using one or more of a capacitor,inductor, varactor, and combinations of one or more of these; and/ordriven from multiple feed points.

In some embodiments, one or more external devices 500 comprise a firstantenna 540 and a second antenna 540. In these embodiments, the firstantenna 540 can be similar or dissimilar to the second antenna 540. Insome embodiments, a first antenna 540 and a dissimilar second antenna540 are positioned within a single external device 500 (e.g., withinhousing 510). In other embodiments, a first antenna 540 is positioned ina first external device 500, and a dissimilar second antenna 540 ispositioned in a second external device 500. The similarity ordissimilarity of the antennas can be configured to enhance one or moredesign and/or performance parameters selected from the group consistingof: implantable device 200 operation depth; polarization; powerefficiency; a radiation footprint; directional gain; beam shaping and/orfocusing; sensitivity to implantable device 200 placement; patientcomfort; patient usability; data transfer; and combinations of one ormore of these. In some embodiments, the first antenna 540 can beoptimized for a different design parameter than the second antenna 540,and each antenna 540 can be activated independently or simultaneously torealize both benefits. In some embodiments, the first antenna 540 can besimilar to the second antenna 540 and placed in an array to increase theradiation footprint or placed in different external locations to operatewith multiple implantable devices 200 implanted at different sites.

In some embodiments, a first external antenna 540 and a second externalantenna 540 transmit power and/or data to a single implantable antenna240. In some embodiments, a first antenna 540 and a second antenna 540can transmit power and/or data to the one or more antennas 240,simultaneously or sequentially. In sequential power and/or datatransfers, a first external device 500 comprising a first one or moreantennas 540 can be replaced (e.g., swapped) with a second externaldevice 500 comprising a second one or more antennas 540. Alternativelyor additionally, sequential power and/or data transfer can be initiatedby one or more of the following conditions: when the first externalantenna 540 moves (e.g., moves relative to the implanted antenna 240);when a second external device 500 comprising the second antenna 540 isturned on or otherwise activated; when the second antenna 540 providesimproved power and/or data transfer to the antenna 240 than is providedby the first antenna 540; and/or when power received from the firstantenna 540 decreases (e.g., decreases below a threshold). In someembodiments, an antenna 240 receives power from a first antenna 540 anda second antenna 540, but only receives data from the first antenna 540.In some embodiments, a first antenna (e.g., an antenna 240 or an antenna540) is driven with a different carrier signal than a second antenna(e.g., an antenna 240 or an antenna 540). The two carrier signals cancomprise differences in amplitudes and/or relative phases as compared toeach other. Each carrier signal can include a data transmission (e.g.,data to be transmitted to an implantable device 200 from an externaldevice 500 or to an external device 500 from an implantable device 200).

One or more transmitters 530 (singly or collectively externaltransmitter 530) can each comprise one or more external transmittersthat drive one or more antennas 540 (e.g., one or more antennas 540positioned in a single external device 500 or multiple external devices500). Transmitter 530 is operably attached to antenna 540 and isconfigured to provide one or more drive signals to antenna 540, such asone or more power signals and/or data signals transmitted to one or moreimplantable devices 200 of implantable system 20. In some embodiments,one or more transmission signals are delivered at a frequency rangebetween 10 MHz and 100 MHz, such as approximately 40.68 MHz. In someembodiments, transmitter 530 comprises a transmitter that operates in afrequency range between 0.1 GHz and 10.6 GHz, such as a transmitter thatoperates in a frequency range between 0.1 GHz and 3.0 GHz, between 0.4GHz and 1.5 GHz, between approximately 0.902 GHz and 0.928 GHz, or in afrequency range proximate to 866 MHz, or approximately between 863 MHzand 870 MHz. Transmitter 530 can comprise a transmitter that produces atransmission signal with a power level between 10 mW and 4 W, such as apower level between 10 mW and 400 mW. Transmitter 530 can comprise atransmitter that produces a transmission signal with a power levelbetween 0.1 W and 4.0 W, such as a transmission signal with a powerlevel between 0.1 W and 2.0 W or between 0.2 W and 1.0 W.

As described herein, one or more external devices 500 can be configuredto transmit data (e.g., configuration data) to one or more implantabledevices 200, such as via a data transmission produced by transmitter 530and sent to one or more antennas 540. In some embodiments, a transmitter530 is configured to perform data modulation comprising amplitude shiftkeying with pulse width modulation. In these embodiments, thetransmitter can be configured to perform multi-level amplitude shiftkeying. The amplitude shift-keying can be configured to provideadjustable-depth modulation between 0-100% depth, such as between 5-75%depth, or such as between 10-50% depth. In some embodiments, one or moreexternal devices 500 transmit data to one or more implantable devices200 using time division multiple access (TDMA). In some embodiments, oneor implantable devices 200 are independently addressable through uniqueidentification (ID) codes. Alternatively or additionally, transmitter530 can be configured to transmit one or more data signals with abandwidth between 1 kHz and 100 MHz, between 0.1 MHz and 100 MHz, orbetween 1 MHz and 26 MHz.

As described herein, one or more external devices 500 can be configuredto transmit power to one or more implantable devices 200, such as via apower transmission produced by transmitter 530 and set to one or moreantennas 540. One or more transmitters 530 can deliver power to one ormore implantable devices 200 simultaneously or sequentially. In someembodiments, one or more transmitters 530 are configured to adjust thelevel of power transmitted to one or more implantable devices 200, suchas by adjusting one or more duty cycling parameters. In theseembodiments, power transmitted can be adjusted to: set a power transferbased on a stimulation level produced by implantable system 20; preventoversaturation; to reduce interference with implantable system 20 datatransmissions (e.g., when one or more implantable devices 200 arefurther configured to transmit data to external system 50); set a powertransfer based on charge information and/or discharge informationrelated to an implantable device 200 (e.g., charge rate and/or dischargerate of an implantable energy storage assembly 270); and combinations ofone or more of these. In some embodiments, implantable system 20comprises a first receiver 230 (e.g., of a first implantable device 200)and a second receiver 230 (e.g., of a second implantable device 200′).One or more transmitters 530 can be configured to transmit a first powertransmission to the first receiver 230, and a second power transmissionto the second receiver 230. The first power transmission and the secondpower transmission can be adjusted or otherwise be different, such as toprevent oversaturation.

In some embodiments, transmitter 530 (and/or another component ofexternal system 50) is further configured as a receiver, such as toreceive data from implantable system 20. For example, a transmitter 530can be configured to receive data via one or more antennas 240 of one ormore implantable devices 200. Data received can include patientinformation (e.g., patient physiologic information, patient environmentinformation or other patient information) and/or information related toan implantable system 20 parameter (e.g., an implantable device 200stimulation parameter and/or other configuration parameter as describedherein).

In some embodiments, transmitter 530 comprises a first transmitter totransmit power and/or data to one or more implantable devices 200, and asecond transmitter to transmit data to a different device, as describedherein. In these embodiments, a second transmitter of transmitter 530can be configured to transmit data to tool 60 or another device such asan external programmer 550, cell phone; computer; tablet; computernetwork such as the internet or a LAN; and combinations of one or moreof these. In some embodiments, the second transmitter of transmitter 530comprises a wireless transmitter; a Bluetooth transmitter; a cellulartransmitter; and combinations of one or more of these. In someembodiments, a functional element 560 comprises a transmitter such as aBluetooth transmitter.

Each power supply 570 (singly or collectively power supply 570) can beoperably attached to a transmitter 530, and one or more other electricalcomponents of each external device 500. Power supply 570 can comprise apower supplying and/or energy storage element selected from the groupconsisting of: battery; replaceable battery (e.g., via a battery door ofhousing 510); rechargeable battery; AC power converter; capacitor; andcombinations of one or more of these. In some embodiments, power supply570 comprises two or more batteries, such as two or more rechargeablebatteries, such as to allow the first battery to be replaced (e.g.,serially replaced) by the second battery. In some embodiments, powersupply 570 is configured to provide a voltage of at least 3V. In someembodiments, power supply 570 is configured to provide a capacitybetween 1 Watt-hour and 75 Watt-hours, such as a battery or capacitorwith a capacity of approximately 5 Watt-hours. In some embodiments,power supply 570 comprises an AC power source.

Each external programmer 550 (singly or collectively external programmer550 or programmer 550) comprises a programming device configured tocontrol one or more components of apparatus 10. Programmer 550 cancomprise a user interface 555. Programmer 550 can send and/or receivecommands to and/or from one or more external devices 500 via a wirelessor wired connection (wired connection not shown but such as one or moreinsulated conductive wires). In some embodiments, one or more externaldevices 500 comprise programmer 550, such as when user interface 555 isintegrated into housing 510 of external device 500. In some embodiments,apparatus 10 comprises multiple programmers 550.

External programmer 550 can be configured to adjust one or moreparameters of apparatus 10, such as a stimulation parameter (e.g., astimulation waveform parameter as described herein); a sensingparameter; a therapy parameter; a data recording parameter (e.g., apatient data recording parameter and/or an implantable device 200 datarecording parameter); power transfer; data rate; activity of one or moreexternal transmitters 530; activity of one or more external antennas540; a functional element 260 parameter; a functional element 560parameter; and combinations of one or more of these, such as isdescribed hereabove. Programmer 550 can be further configured to provideinformation, such as patient physiologic information recorded by one ormore implantable devices 200, or apparatus 10 information, such asperformance and/or configuration information (singly or collectively“status information”) of one or more external devices 500 and/orimplantable devices 200. In some embodiments, the programmer 550 usesinformation recorded by one or more implantable devices 200, apparatus10 information, and/or information from external devices 500 to adaptconfiguration parameters of one or more components of apparatus 10.

In some embodiments, external programmer 550 can be configured toconfirm that an adequate power transmission and/or an adequate datatransmission has occurred between one or more external devices 500 andone or more implantable devices 200. In these embodiments, programmer550 can comprise diagnostic assembly 91 described herebelow, orotherwise be configured to detect one or more of: power transmission tothe implantable system 20 (e.g., to detect power transmission toimplantable system 20 below a threshold); power transmission to theimplantable system 20 trending in an undesired direction; improperand/or inadequate data transfer to the implantable system 20; andcombinations of one or more of these. In some embodiments, theprogrammer 550 monitors power transfer in real time and adjusts powertransmission accordingly to optimize the rectifier 232 efficiency of oneor more implantable devices 200. In some embodiments, apparatus 10 canbe configured to adjust (e.g., in real time) the power transmission fromone or more external devices 500 of external system 50 to one or moreimplantable devices 200 of implantable system 20, such as to optimize orotherwise improve an efficiency of apparatus 10, such as to improve theefficiency of transmissions between an external device 500 and animplantable device 200. These adjustments can include adjustment to oneor more of: power transmission amplitude, duty cycle, frequency, phase,and periodicity.

In some embodiments, programmer 550 and/or another component ofapparatus 10 comprises a matching network configured to match theimpedance of one or more antennas 540 to one or more transmitters 530.The matching network can comprise an adjustable matching network. Thematching network can comprise a directional coupler configured tomeasure a reflection coefficient. A transmitter 530 can comprise anoutput, and a programmer 550 can be configured to monitor a standingwave pattern at the output of the transmitter 530.

In some embodiments, external programmer 550 comprises a lookup table ofstimulation signal waveform patterns, such as to allow a clinician,patient and/or other operator of apparatus 10 to select a predeterminedstimulation pattern. In some embodiments, programmer 550 comprises a setof adjustable stimulation signal parameters configured to be varied toallow an operator to construct customized waveforms, such as to vary oneor more stimulation parameters described hereabove. In some embodiments,the programmer 550 is configured to allow an operator to create acustomized waveform by specifying an amplitude of one or more discretepulses or steps of a stimulation signal.

In some embodiments, external programmer 550 comprises a transmitterconfigured to transmit data to tool 60 or another device such as a cellphone; computer; tablet; computer network such as the internet or a LAN;and combinations of one or more of these. In these embodiments,programmer 550 can comprise a wireless transmitter; a Bluetoothtransmitter; a cellular transmitter; and combinations of one or more ofthese. In some embodiments, external programmer 550 comprises a receiverconfigured to receive data, or a transceiver configured to both transmitand receive data.

User interface 555 of external programmer 550 can comprise one or moreuser input components and/or user output components, such as a componentselected from the group consisting of: keyboard; mouse; keypad; switch;membrane switch; touchscreen; display; audio transducer such as aspeaker or buzzer; vibrational transducer; light such as an LED; andcombinations of one or more of these.

In some embodiments, one or more components of external system 50 and/orother external component of apparatus 10, comprises one or morefunctional elements 560, such as functional elements 560 a and/or 560 b(singly or collectively functional element 560), shown positioned inprogrammer 550 and in external device 500, respectively. Each functionalelement 560 can comprise a sensor, an electrode, an energy deliveryelement, an agent delivery element, a magnetic field generatingtransducer, and/or any transducer. In some embodiments, one or morefunctional elements 560 comprise a transducer selected from the groupconsisting of: light; light emitting diode; wireless transmitter;Bluetooth device; mechanical transducer; piezoelectric transducer;pressure transducer; temperature transducer; humidity transducer;vibrational transducer; audio transducer; speaker; and combinations ofone or more of these. In some embodiments, functional element 560comprises a needle, a catheter (e.g., a distal portion of a catheter),an iontophoretic element or a porous membrane, such as an agent deliveryelement configured to deliver one or more agents contained (e.g., one ormore agents in a reservoir, such as reservoir 525 described herebelow)within an external device 500 and delivered into the patient (e.g., intosubcutaneous tissue, into muscle tissue and/or into a blood vessel suchas a vein).

In some embodiments, the functional element 560 can comprise anelectrode for sensing electrical activity and/or delivering electricalenergy. In some embodiments, apparatus 10 is configured to causestochastic resonance, and the addition of white noise can enhance thesensitivity of nerves to be stimulated and/or boost weak signals to berecorded by the one or more functional elements 260.

In some embodiments, one or more functional elements 560 comprise asensor, such as a sensor configured to record data related to a patientparameter (e.g., a patient physiologic parameter), an external system 50parameter and/or an implantable system 20 parameter. In someembodiments, operation of one or more implantable devices 200 (e.g.,stimulation energy delivered by one or more implantable devices 200) isconfigured to be delivered based on the data recorded by one or moresensor-based functional elements 560, such as in a closed-loop energydelivery mode.

Functional element 560 can comprise one or more sensors selected fromthe group consisting of: electrode; sensor configured to recordelectrical activity of tissue; blood glucose sensor such as an opticalblood glucose sensor; pressure sensor; blood pressure sensor; heart ratesensor; inflammation sensor; neural activity sensor; muscular activitysensor; pH sensor; strain gauge; accelerometer; gyroscope; GPS;respiration sensor; respiration rate sensor; temperature sensor;magnetic sensor; optical sensor; MEMs sensor; chemical sensor; hormonesensor; impedance sensor; tissue impedance sensor; body position sensor;body motion sensor; physical activity level sensor; perspiration sensor;patient hydration sensor; breath monitoring sensor; sleep monitoringsensor; food intake monitoring sensor; urine movement sensor; bowelmovement sensor; tremor sensor; pain level sensor; orientation sensor;motion sensor; and combinations of one or more of these.

Functional element 560 can comprise one or more sensors configured torecord data regarding a patient parameter selected from the groupconsisting of: blood glucose; blood pressure; EKG; heart rate; cardiacoutput; oxygen level; pH level; pH of blood; pH of a bodily fluid;tissue temperature; inflammation level; bacteria level; type of bacteriapresent; gas level; blood gas level; neural activity; neural spikes;neural spike shape; action potential; local field potential (LFP); EEG;muscular activity; electrical activity produced by skeletal muscles(e.g., as measured using electromyography, EMG); gastric volume;peristalsis rate; impedance; tissue impedance; electrode-tissueinterface impedance; physical activity level; pain level; body position;body motion; organ motion; respiration rate; respiration level;perspiration rate; sleep level; sleep cycle; digestion state; digestionlevel; urine production; urine flow; bowel movement; tremor; ionconcentration; chemical concentration; hormone level; viscosity of abodily fluid; patient hydration level; and combinations of one or moreof these.

Functional element 560 can comprise one or more sensors configured torecord data representing a parameter of external system 50 or anycomponent of apparatus 10. Functional element 560 can comprise one ormore sensors selected from the group consisting of: an energy sensor; avoltage sensor; a current sensor; a temperature sensor (e.g., atemperature of one or more components of external device 500 orprogrammer 550); an antenna matching and/or mismatching assessmentsensor; power transfer sensor; link gain sensor; power use sensor;energy level sensor; energy charge rate sensor; energy discharge ratesensor; impedance sensor; load impedance sensor; instantaneous powerusage sensor; average power usage sensor; bit error rate sensor; signalintegrity sensor; and combinations of one or more of these. Apparatus 10can be configured to analyze (e.g., via controller 250 describedherebelow) the data recorded by functional element 560 to assess one ormore of: power transfer; link gain; power use; energy within powersupply 570; performance of power supply 570; expected life of powersupply 570; discharge rate of power supply 570; ripple or othervariations of power supply 570; matching of antennas 240 and 540;communication error rate between implantable device 200 and externaldevice 500; integrity of transmission between implantable device 200 andexternal device 500; and combinations of one or more of these.

In some embodiments, one or more functional elements 560 are positionedon a housing 510. A functional element 560 can comprise a bodyconduction sensor, such as a body conduction sensor configured to recordand/or receive data via skin conduction. A functional element 560 can beconfigured to record data associated with stimulation delivered by oneor more implantable devices 200 (e.g., record data associated withstimulation energy delivered by one or more functional elements 260),such as to provide closed loop or semi-closed loop stimulation. Afunctional element 560 can be configured to record temperature, such aswhen apparatus 10 is configured to deactivate or otherwise modify theperformance of an external device 500 when the recorded temperature(e.g., patient temperature and/or external device 500 temperature)exceeds a threshold.

In some embodiments, external programmer 550 and/or an external device500 can comprise a temperature sensor, such as functional elements 560 aand 560 b shown, respectively. The temperature-based functional element560 can be positioned proximate a portion of programmer 550, housing 510and/or one or more antennas 540 (e.g., to measure the temperature of oneor more portions of a programmer 550 and/or external device 500). Inthese embodiments, the temperature data recorded by the functionalelement 560 is used to adjust one or more of: matching network;stimulation level (e.g., stimulation energy delivered by one or moreimplantable devices 200); power transmission level (e.g., level of powertransmitted between one or more external devices 500 and one or moreimplantable devices 200); and combinations of one or more of these. Insome embodiments, the temperature sensor-based functional element 560 isa part of a safety mechanism that deactivates programmer 550 and/or anexternal device 500 if the recorded temperature exceeds a threshold.Alternatively or additionally, a temperature sensor-based functionalelement 560 can be configured to measure temperature of the patient,such as when placed on housing 510, such as to adjust energy and/oragent delivery performed by implantable device 200 based on the recordedpatient temperature.

Implantable system 20 comprises one or more implantable devices 200,such as one or more implantable devices 200 provided sterile orconfigured to be sterilized for implantation into the patient. A firstimplantable device 200 can be of similar or dissimilar construction andarrangement to a second implantable device 200. Each implantable device200 can be configured to treat a patient (e.g., treat pain of thepatient) and/or record patient information, such as by delivering energyand/or an agent to tissue and/or by recording one or more physiologicparameters of tissue.

One or more portions of an implantable device 200 or other component ofimplantable system 20 can be configured to be visualized or contain avisualizable portion or other visualizable element, such as visualizableelement 222 shown. Visualizable element 222 can comprise a materialselected from the group consisting of: radiopaque material;ultrasonically reflective material; magnetic material; and combinationsof one or more of these. In these embodiments, each implantable device200 can be visualized (e.g., during and/or after implantation) via animaging device such as a CT, X-ray, fluoroscope, ultrasound imagerand/or MRI.

In some embodiments, implantable system 20 comprises multipleimplantable devices 200 (e.g., implantable device 200 and implantabledevice 200′ shown in FIG. 1) and implantable system 20 comprises a“multi-point ready” system, in which the operation (e.g., energydelivery, agent deliver, data recording and/or other function) of themultiple implantable devices 200 is performed simultaneously,asynchronously, and/or sequentially. The implantable devices 200 can bepart of a network including one or more external devices 500 (e.g.,external device 500 and external device 500′ shown in FIG. 1) in whichthe treating of a patient and/or the recording of patient informationrelies on operation of the implantable devices 200 at one or moreimplantation sites in a synchronized, asynchronized, and/or otherwisecoordinated way. The synchronization or otherwise coordination can becontrolled by a single or multiple external devices 500, which canfurther be synchronized to a single clock. Each implantable device 200of implantable system 20 can receive a power signal and/or a data signalfrom one or more external devices 500. In some embodiments of themulti-point ready implantable system 20, each implantable device 200comprises a unique ID, such that each implantable device 200 can beindividually addressed (e.g., receive unique signals from externalsystem 50). In some embodiments, external system 50 transmitshigh-bandwidth signals to implantable system 20, such that time-domainmultiple access communication can be performed while operating in nearreal time. In some embodiments, implantable system 20 is configured as amulti-point ready system such that stimulation energy delivered byimplantable system 20 is independent of power received by implantablesystem 20 from external system 50.

Two implantable devices 200, or two discrete components of a singleimplantable device 200 (e.g., two components comprising or positioned indifferent housings), can be attached to each other by a connectingfilament as defined hereabove. In some embodiments, a connectingfilament comprises a user-attachable (e.g., clinician-attachable)connector on at least one end. The filament connector is configured tooperably attach to a mating connector on a component (e.g., a housing210) of an implantable device 200.

Each implantable device 200 is configured to receive power and/or data(e.g., implantable system 20 configuration data) from one or moreexternal devices 500. In some embodiments, one or more implantabledevices 200 are configured to receive both power and data (e.g.,simultaneously and/or sequentially) from one or more external devices500. In some embodiments, a single external device 500 sends powerand/or data to multiple implantable devices 200. Alternatively oradditionally, a single implantable device 200 can receive power and/ordata from multiple external devices 500. In some embodiments, a firstexternal device 500 is positioned on or near the patient's skin at alocation proximate an implanted first implantable device 200, and asecond external device 500 is positioned on or near the patient's skin(generally “on” the patient's skin) at a location proximate an implantedsecond implantable device 200. In these embodiments, the first externaldevice 500 transmits data and/or power to at least the first implantabledevice 200 and the second external device 500 transmits data and/orpower to at least the second implantable device 200.

Each implantable device 200 can comprise one or more functional elements260, configured to stimulate, deliver energy to, deliver an agent to,record information from and/or otherwise interface with the patient.Alternatively or additionally, the one or more functional elements 260can be configured to record patient information. Each implantable device200 can comprise housing 210, receiver 230, controller 250, energystorage assembly 270 and/or one or more antennas 240, each described indetail herein. In some embodiments, antenna 240 comprises an antennaassembly, such as such as a shielded or other antenna assembly, such asany antenna assembly 1040 described herein. Each functional element 260can comprise a sensor and/or any transducer, as described in detailherein. One or more functional elements 260 can be positioned on a lead265 (e.g., a flexible filament including wires or other conductors thatconnect each functional element to electronics within housing 210). Eachimplantable device 200 can comprise one or more leads 265, such as twoleads attached to a single housing 210, or a first lead 265 attached toa first housing 210 and a second lead 265 attached to a second housing210. Each implantable device 200 can further comprise one or more anchorelements 221, as described in detail herebelow.

In some embodiments, one or more implantable devices 200 are furtherconfigured to transmit data to one or more external devices 500, such asvia one or more antennas 240 transmitting a signal to one or moreantennas 540, or otherwise. Data transmitted by an implantable device200 can comprise patient information (e.g., patient physiologicinformation recorded by one or more functional elements 260 configuredas a physiologic sensor), or implantable device 200 information (e.g.,data recorded by one or more functional elements 260 configured as asensor and positioned in implantable device 200, or other implantabledevice 200 configuration and/or performance data).

Housing 210 of each implantable device 200 can comprise one or morerigid and/or flexible materials which surround various components, suchas antenna 240, energy storage assembly 270, controller 250 and/orreceiver 230 as shown in FIG. 1. In some embodiments, one or morefunctional elements 260 are positioned in, on and/or within housing 210.In some embodiments, housing 210 surrounds a substrate, such as aflexible and/or foldable printed circuit board, such as multiplediscrete or continuous printed circuit boards positioned in differentplanes (e.g., a flexible or foldable printed circuit board).

Housing 210 can comprise one or more shapes or combination of shapes,such as one or more shapes selected from the group consisting of: disc;pill; cylinder; sphere; oblate spheroid; dish-like shape; bowl-likeshape; cone; rectangular prism; trapezoidal prism; a portion of atoroid; and combinations of one or more of these.

Housing 210 can comprise a major axis and a minor axis, definedhereabove. In some embodiments, housing 210 comprises a major axis lessthan or equal to 20 mm, such as a major axis less than or equal to 15mm, 12 mm or 10 mm. In some embodiments, housing 210 comprises a minoraxis less than or equal to 8 mm, such as a minor axis less than or equalto 6 mm, or less than or equal to 5 mm. Housing 210 can comprise a wallthickness between 0.2 mm and 1.0 mm, such as a wall thickness between0.2 mm and 0.5 mm, such as a wall thickness of approximately 0.3 mm.Housing 210 can comprise a displacement volume less than or equal to2000 mm³, such as less than or equal to 600 mm³.

Housing 210 can comprise one or more portions that are transmissive toradiofrequency (RF) signals. In some embodiments, housing 210 comprisesglass. In some embodiments, housing 210 comprises a material selectedfrom the group consisting of: glass; ceramic; stainless steel; titanium;polyurethane; an organic compound; liquid crystal polymer (LCP); gold;platinum; tungsten; epoxy; a thermoplastic; a thermoset plastic; andcombinations of one or more of these. In some embodiments, one or moreportions of housing 210 comprises one or more coatings, such as one ormore coatings configured to cause or prevent a physiologic reactionand/or a coating configured to block (e.g., shield) an electromagnetictransmission.

Housing 210 can comprise one or more passageways or other feedthroughs,such as for the passage of a lead, wire, optical fiber, fluid deliverytube, mechanical linkage and/or other conduit through a wall of housing210, such as is described in applicant's International PCT PatentApplication Serial Number PCT/US2016/016888, titled “Medical Apparatusincluding an Implantable System and an External System”, filed Feb. 5,2016; the content of which is incorporated herein by reference in itsentirety for all purposes.

In some embodiments, one or more inner or outer surfaces (or portions ofsurfaces) of housing 210 includes an insulating and/or shielding layer(e.g., a conductive electromagnetic shielding layer), such as innercoating 219 a and/or outer coating 219 b shown (singly or collectivelycoating 219). Coating 219 can comprise an electrically insulating and/ora thermally insulating layer or other coating. In some embodiments, oneor more portions of housing 210 comprise an electrically shieldingcoating 219, while other portions are transmissive to electromagneticsignals such as radiofrequency signals.

In some embodiments, housing 210 comprises an array of feedthroughs, notshown. In some embodiments, housing 210 is surrounded by a covering,such as a flexible and/or non-conductive covering, such as a coveringmade of an elastomer.

In some embodiments, one or more implantable devices 200 comprises oneor more anchor elements configured to secure one or more portions ofimplantable device 200 to tissue, such as anchor element 221 shownpositioned on housing 210. Anchor element 221 can comprise one or moreanchoring elements selected from the group consisting of: a sleeve suchas a silicone sleeve; suture tab; suture eyelet; bone anchor, wireloops; porous mesh; penetrable wing; penetrable tab; bone screw eyelet;tine; pincers; suture slits; and combinations of one or more of these.

One or more antennas 240 (singly or collectively antenna 240) can beconfigured to receive power and/or data, and receiver 230 can receivethe power and/or data from the one or more antennas 240. Each antenna240 can comprise one or more implantable antennas, such as one or moreantennas positioned within housing 210, and/or one or more antennaselectrically attached to a connecting filament. In some embodiments, oneor more implantable devices 200 comprise at least two antennas 240, orat least three antennas 240. Antenna 240 can be configured to receivepower and/or data from one or more external devices 500, such that anattached receiver 230 receives the power and/or data. In someembodiments, implantable system 20 comprises at least two implantabledevices 200, each of which comprise one or more (e.g., two or three)antennas 240 which are positioned within a housing 210 and/orelectrically tethered to a housing 210. In some embodiments, animplantable device 200 comprises a first antenna 240 positioned in afirst plane and a second antenna 240 positioned in a second plane. Thefirst plane and second plane can be relatively orthogonal planes, orplanes oriented between 30° and 90° relative to each other, such asbetween 40° and 90°, approximately 30°, approximately 45° and/orapproximately 60° relative to each other. In some embodiments, animplantable device 200 comprises a first antenna 240 positioned in afirst plane, a second antenna 240 positioned in a second plane, and athird antenna 240 positioned in a third plane.

In some embodiments, implantable device 200 comprises one or moreantennas 240 positioned on a substrate, such as a printed circuit board(PCB), a flexible printed circuit board and/or a foldable substrate(e.g., a substrate comprising rigid portions and hinged portions). Insome embodiments, the substrate can be folded or otherwise pivoted toposition the various antennas 240 on differently oriented planes, suchas multiple planes oriented between 5° and 90° relative to each other,such as two antennas 240 positioned on two planes oriented between 30°and 90° or between 40° and 90° relative to each other, or three antennas240 positioned on three planes oriented between 5° and 60° relative toeach other. Two or more antennas 240 can be positioned on two or moredifferent planes that are approximately 45° relative to each other, orapproximately 60° or approximately 90° relative to each other.

Implantable device 200 can comprise three antennas 240. In someembodiments, a first antenna 240 can comprise an electrical dipoleantenna, and the second and third antennas 240 can be positioned indifferent planes than the first antenna 240. In some embodiments, thethree antennas 240 each comprise a loop antenna, such as when each loopantenna is positioned on a different plane. In some embodiments, a firstantenna 240 comprises an electrical dipole antenna, and a second antenna240 and a third antenna 240 each comprise a loop antenna. In theseembodiments, the second antenna 240 and the third antenna 240 can bepositioned relatively orthogonal to each other (e.g., positioned on tworelatively orthogonal planes). In some embodiments, a first antenna(e.g., an electrical dipole antenna) is positioned outside of housing210, while a second antenna (e.g., a loop antenna) and a third antenna(e.g., a loop antenna) are each positioned on, in and/or within housing210. In some embodiments, implantable device 200 can comprise one ormore antennas 240 in which any combination of antenna types (asdescribed herein) are used in combination.

One or more antennas 240 can comprise an antenna selected from the groupconsisting of: loop antenna; multiple-turn loop antenna; planar loopantenna; coil antenna; dipole antenna; electric dipole antenna; magneticdipole antenna; patch antenna; loaded dipole antenna; concentric loopantenna; loop antenna with ferrite core; and combinations of one or moreof these. One or more antennas 240 can comprise a loop antenna, such asan elongated loop antenna or a multiple-turn loop antenna.

One or more antennas 240 can comprise a multi-turn spiral loop antenna,such as a multi-turn spiral loop antenna configured to desensitizecoupling sensitivity and/or boost input voltage. In some embodiments,one or more antennas 240 comprise multiple concentric loops with varieddimensions, such as concentric loops configured to desensitize couplingsensitivity. In these embodiments, the multiple concentric loops can be:connected in parallel and driven from the same feed point; driven fromthe same feed point and connected using one or more of a capacitor,inductor, varactor, and combinations of one or more of these; and/ordriven from multiple feed points.

One or more antennas 240 can comprise a minor axis and a major axis. Insome embodiments, one or more antennas 240 comprise a minor axis between1 mm and 8 mm, such as between 2 mm and 5 mm. In some embodiments, oneor more antennas 240 comprise a major axis between 3 mm and 15 mm, suchas between 4 mm and 8 mm. In some embodiments, one or more antennas 240comprise a major axis above 3 mm, such as between 3 mm and 15 mm, suchas when the antenna 240 is positioned outside of housing 210.

One or more antennas 240 can comprise a foldable and/or unfoldableantenna, such as is described in applicant's U.S. patent applicationSer. No. 14/975,358, titled “Method and Apparatus for Minimally InvasiveImplantable Modulators”, filed Dec. 18, 2015, the content of which isincorporated herein by reference in its entirety for all purposes.

One or more antennas 240 can be positioned inside of housing 210.Alternatively or additionally, one or antennas 240 can be positionedoutside of housing 210.

Implantable system 20, one or more implantable devices 200 and/or one ormore antennas 240 can be configured to be positioned at a desired depthbeneath the patient's skin, such as at a depth between 0.5 cm and 7.0cm, such as a depth of between 1.0 cm and 3.0 cm.

One or more energy storage assemblies 270 (singly or collectively energystorage assembly 270) can comprise one or more implantable energystorage components, such as one or more batteries (e.g., rechargeablebatteries) and/or capacitors (e.g., a supercapacitor). Energy storageassembly 270 can be configured to provide power to one or more of: oneor more functional elements 260; controller 250; receiver 230; andcombinations of one or more of these. In some embodiments, energystorage assembly 270 further provides power to one or more antennas 240and/or circuitry configured to transmit data via antenna 240. In someembodiments, energy storage assembly 270 includes digital control forcharge/discharge rates, voltage outputs, current outputs, and/or systempower distribution and/or management.

Energy storage assembly 270 can comprise one or more capacitors with asingle or collective capacitance between 0.01 μF and 10 F, such as acapacitance between 1 μF and 1.0 mF, or between 1 μF and 10 μF. Theenergy storage assembly 270 can comprise one or more capacitors withcapacitance between 1 mF and 10 F, such as when energy storage assembly270 comprises a super-capacitor and/or an ultra-capacitor. Such largecapacitance can be used to store sufficient charge to maintain operation(e.g., maintain delivery of stimulation energy and/or delivery of anagent) without the use (e.g., sufficient proximity) of an associatedexternal device 500. A capacitor or other energy storage element (e.g.,a battery) can be chosen to provide sufficient energy to maintainoperation for at least 30 seconds, at least 2 minutes, at least 5minutes, at least 30 minutes, and up to several hours or more (e.g.,during showering, swimming or other physical activity). In someembodiments, energy storage assembly 270 is configured to providecontinuous and/or intermittent stimulation energy for at least onecharge-balanced pulse (e.g., for the duration of at least onecharge-balanced pulse). In some embodiments, a capacitor, battery orother energy storage element is configured to provide stimulation energywithout receiving externally supplied power for periods of at least 1hour, at least 1 day, at least 1 month or at least 1 year. Energystorage assembly 270 can comprise one or more capacitors with abreakdown voltage above 1.0V, such as a breakdown voltage above 1.5V,4.0V, 10V, or 15V. In some embodiments, energy storage assembly 270 cancomprise capacitors distributed outside of housing 210, such as when oneor more capacitors are distributed along lead 265. Energy storageassembly 270 can comprise one or more capacitors with low self-leakage,such as to maintain stored energy for longer periods of time.

In some embodiments, energy storage assembly 270 comprises a temporaryenergy storage component, such as a super-capacitor, configured to storea sufficient quantity of energy to provide uninterrupted stimulation,such as during time periods in which the link gain may be of poorquality or it may be temporarily unavailable (e.g., an external device500 not being in place such as during a shower, swimming, and the like).An energy storage assembly 270 comprising an ultra-capacitor,super-capacitor or flexible battery can be charged via the wirelesspower transmission of the present inventive concepts, such as to store asufficient amount of energy for one or more functional elements 260 todelivery stimulation energy during subsequent (intended or unintended)unavailability of one or more external devices 500 (e.g., an externaldevice 500 is intentionally removed or unintentionally falls off orotherwise loses its position sufficiently proximate one or moreimplantable devices 200). An energy storage assembly 270 comprising oneor more high capacity energy storage components can be beneficial inapplications where therapy interruption provides a significant risk oris otherwise relatively unacceptable, such as for life supporttherapies, cardiac resynchronization therapies, and the like. The highcapacity energy storage components of energy storage assembly 270 can bepositioned in an assembly positioned within housing 210, on an inner orouter surface of housing 210, within a separate housing, and/or withinlead 265.

One or more controllers 250 (singly or collectively controller 250) canbe configured to control one or more functional elements 260, such as afunctional element 260 comprising a stimulation-based transducer (e.g.,an electrode or other energy delivery element) and/or a sensor (e.g., aphysiologic sensor and/or a sensor configured to monitor an implantabledevice 200 parameter). In some embodiments, controller 250 is configuredto transmit a stimulation signal (e.g., transmit stimulation energyconfigured in one or more stimulation waveforms) to one or morefunctional elements 260 (e.g., one or more functional elements 260comprising an electrode and/or other energy delivery element),independent of the power signal received by one or more antennas 240(e.g., independent of power transmitted by external system 50), such asby using energy stored in energy storage assembly 270. In theseembodiments, the power signal and/or the RF path for the power signalcan be adjusted to optimize power efficiency (e.g., by tuning matchingnetwork on transmitter 530 and/or receiver 230; configuring antennas 540and/or 240 in an array; tuning operating frequency; duty cycling thepower signal; adjusting antenna 540 and/or 240 position; and the like),and a stimulation signal can be precisely delivered (e.g., by usingenergy stored on energy storage assembly 270 and generating stimulationsignal locally on the implantable device 200) to ensure clinicalefficacy. Also, if the power signal transmission (also referred to as“power link”) is perturbed unexpectedly, the stimulation signal can beconfigured so that it is not significantly affected (e.g., unaffected).In some configurations, the stimulation signal being delivered by one ormore implantable devices 200 can be insensitive to interference that maybe present. In these embodiments, a power transmission signal andstimulation signal can vary in one or more of: amplitude; changes inamplitude; average amplitude; frequency; changes in frequency; averagefrequency; phase; changes in phase; average phase; waveform shape; pulseshape; duty cycle; polarity; and combinations of one or more of these.

Controller 250 can receive commands from receiver 230, such as one ormore commands related to one or more implantable device 200configuration parameters selected from the group consisting of:stimulation parameter; data rate of receiver; data rate of datatransmitted by the first implantable device 200 at least one implantableantenna 240; functional element 260 configuration; state of controller250; antenna 240 impedance; clock frequency; sensor configuration;electrode configuration; power management parameter; energy storageassembly parameter; agent delivery parameter; sensor configurationparameter; and combinations of one or more of these.

In some embodiments, one or more functional elements 260 comprise astimulation element configured to deliver energy (e.g., one or moreelectrodes configured to deliver monopolar or bipolar electrical energy)to tissue, and controller 250 is configured to control the energydelivery, such as to control one or more stimulation parameters asdescribed herein. Each of these stimulation parameters can be heldrelatively constant, and/or varied, such as a variation performed in acontinuous or intermittent manner. In some embodiments, one or morestimulation parameters are varied in a random or pseudo-random(hereinafter “random”) manner, such as a variation performed byapparatus 10 using a probability distribution as described herebelow. Insome embodiments, stimulation (e.g., stimulation comprising highfrequency and/or low frequency signal components) is varied randomly toeliminate or at least reduce synchrony of neuronal firing with thestimulation signal (e.g., to reduce paresthesia or other patientdiscomfort). In some embodiments, one or more functional elements 260comprise a stimulation element configured to stimulate a target (e.g.,nerve tissue such as spinal nerve tissue and/or peripheral nervetissue). The amount of stimulation delivered to the target can becontrolled by varying a parameter selected from the group consisting of:functional element 260 size and/or configuration (e.g., electrode sizeand/or configuration); functional element 260 shape (e.g., electrodeshape, magnetic field generating transducer shape or agent deliveringelement shape); shape of a generated electric field; shape of agenerated magnetic field; stimulation signal parameters; andcombinations of one or more of these.

In some embodiments, one or more functional elements 260 comprise anelement configured to deliver electrical energy to tissue (e.g., one ormore electrodes configured to deliver monopolar or bipolar electricalenergy), and controller 250 is configured to control charge balance,such as to actively and/or passively control charge balance, asdescribed herebelow. Charge balance can be essential for patient safetyin electrical stimulation of nerves or other tissue. Imbalancedstimulation waveforms can cause electrode corrosion and/or dissolutionwhich can lead to deposition of toxic materials in tissue, implantrejection, and nerve damage. The stimulation waveform can be balancedsuch that net outflow charge approximately equals net inflow charge.With stimulation waveform amplitudes that can vary between 0.1 mA to 15mA (such as between 0.1 mA and 12 mA, or between 0.1 mA and 10 mA),depending on the treatment, the error in charge balance can be on theorder of 0.001% to 0.01%. Alternatively or additionally, controller 250can comprise AC coupling capacitors that are configured to balancestimulation waveforms passively. The AC coupling capacitance can befairly large (e.g., greater than 10 μF), in order to pass thestimulation waveform with minimal filtering. In some embodiments,apparatus 10 can be configured to perform active charge balancing. Insome embodiments, an implantable device 200 can comprise a preciseresistor in series with a stimulation electrode-based functional element260. The precise resistor can be used to measure outflow and inflowcurrents, such as when controller 250 comprises an analog to digitalconverter (ADC). Controller 250 can integrate current over time during afirst phase in which stimulation energy is delivered, and during asecond phase in which a reverse current is applied (e.g., a reversecurrent used to balance charge). Controller 250 can be configured tobalance the total charge in the two phases, to ensure that the net DCcurrent is approximately zero. The integration can be achieved using ananalog integrator and/or a digital summer of controller 250, withcontroller 250 keeping track of one or more parameters of the pulsesdelivered (e.g., pulses delivered within a train or a burst).Implantable device 200 can comprise a precise series resistancecomprising an on-chip trimmed resistor or an off chip resistor. In someembodiments, implantable device 200 comprises a bank of trimmedresistors that are used to control the net series resistance, such as toadjust resistance based on stimulation amplitude requirements (e.g., totake advantage of the full dynamic range of an ADC of controller 250).In some embodiments, controller 250 comprises a shunt path with anRC-based low pass filter used for both outflow and inflow of current. RCelements of controller 250 can be chosen such that the shunt current isonly a fraction of the stimulation current. Since the same RC elementscan be used for both outflow and inflow current, the precision requiredfor the RC components can be lower. An ADC can be used to sense thevoltage on the capacitor at the end of a stimulation pulse. After thestimulation pulse, the capacitor can be discharged and the polarity ofthe stimulation current can be reversed and set to any amplitude, untilthe capacitor is charged to approximately the same voltage (according tothe ADC precision) as it was charged during the stimulation pulse. TheADC resolution can be high enough to ensure the residual error is lessthan what would cause an undesired charge accumulation. ADC resolutionrequirements can be further reduced by reducing the net capacitance in ashunt RC circuit, to cause accelerated charging of the capacitor. Thecapacitor can be discharged every time the voltage exceeds a certainpredefined threshold, while controller 250 keeps track of the number oftimes the capacitor has been charged and reset. By resetting thecapacitor through a low resistance path, the discharge time can beinsignificant compared to the charge time, reducing the error due todischarge period. Since the net charge equivalent to full scale voltageon the ADC can be divided into multiple cycles, the required resolutionof the ADC to achieve the same residual error can be divided by thenumber of cycles.

In some embodiments, controller 250 is configured to produce astimulation signal comprising a waveform or a waveform pattern(hereinafter stimulation waveform), for one or more functional elements260 configured as a stimulation element (e.g., such that one or morefunctional elements 260 deliver stimulation energy comprising or atleast resembling that stimulation waveform). Controller 250 can producea stimulation signal comprising a waveform selected from the groupconsisting of: square wave; rectangle wave; sine wave; sawtooth;triangle wave (e.g., symmetric or asymmetric); trapezoidal; ramp;waveform with exponential increase; waveform with exponential decrease;pulse shape which minimizes power consumption; Gaussian pulse shape;pulse train; root-raised cosine; bipolar pulses; and combinations of oneor more of these. In some embodiments, controller 250 is configured toproduce a stimulation signal comprising a waveform including acombination of two or more waveforms selected from the group consistingof: square wave; rectangle wave; sine wave; triangle wave (symmetric orasymmetric); ramp; waveform with exponential increase; waveform withexponential decrease; pulse shape which minimizes power consumption;Gaussian pulse shape; pulse train; root-raised cosine; bipolar pulses;and combinations of one or more of these. In some embodiments,controller 250 is configured to construct a custom waveform (e.g., anoperator customized waveform), such as by adjusting amplitude atspecified time steps (e.g., for one or more pulses). In someembodiments, controller 250 is configured to generate a waveformincluding one or more random parameters (e.g., random timing of pulsesor random changes in frequency, rate of change or amplitude).

In some embodiments, controller 250 is configured to provide astimulation signal comprising waveforms and/or pulses repeated at afrequency (e.g., includes a frequency component) between 1.0 Hz and 50KHz, such as between 10 Hz and 500 Hz, between 40 Hz and 160 Hz and/orbetween 5 KHz and 15 KHz. In some embodiments, controller 250 isconfigured to produce a stimulation signal comprising a frequencybetween 1 Hz and 1000 Hz, such as a stimulation signal with a frequencybetween 10 Hz and 500 Hz. In some embodiments, controller 250 isconfigured to produce a stimulation signal comprising a duty cyclebetween 0.1% and 99%, such as a duty cycle between 1% and 10% or between1% and 25%. In some embodiments, controller 250 is configured to producea stimulation signal comprising a frequency modulated stimulationwaveform, such as a stimulation waveform comprising a frequencycomponent (e.g., signal) between 1 kHz and 20 kHz. In some embodiments,controller 250 is configured to produce a stimulation signal comprisinga mix and/or modulation of low frequency and high frequency signals,which can be of any of the waveform types, shapes and otherconfigurations as described herein. In these embodiments, thestimulation signal can comprise low frequency signals between 1 Hz and1000 Hz, and high frequency signals between 600 Hz and 50 kHz, orbetween 1 kHz and 20 kHz. Alternatively or additionally, the stimulationsignal can comprise a train of high frequency signals and bursts of lowfrequency signals, and/or a train of low frequency signals and bursts ofhigh frequency signals. Alternatively or additionally, the stimulationsignal can comprise one or more high frequency signals modulated withone or more low frequency signals, such as one or more high frequencysignals frequency modulated (FM), amplitude modulated (AM), phasemodulated (PM) and/or pulse width modulated (PWM) with one or more lowfrequency signals. The stimulation signal can cycle among differentwaveforms shapes at specified time intervals. The stimulation signal cancomprise a pseudo random binary sequence (PRBS) non-return-to-zero orreturn-to-zero waveform, such as with a fixed and/or time-varying pulsewidth and/or frequency of the pulses.

Controller 250 can comprise a clamping circuit configured to allow fastcharging and/or discharging of the energy storage assembly 270,functional element 260 drivers (e.g., electrode drivers) of controller250, and/or other components of implantable device 200. The clampingcircuit can improve pulse shape by offering additional control and/orconfiguration of rise and fall times in the shape of the waveform (e.g.,to create rapid rise or fall times). In some embodiments, the clampingcircuit can be configured to limit the rise and/or fall time to be lessthan or equal to one-tenth (10%) of the pulse width of an appliedstimulation pulse (e.g., less than or equal to 1 μs rise and/or falltime for a 10 μs stimulation pulse).

In some embodiments, controller 250 comprises a matching networkconfigured to match the impedance of a first antenna 240 with theimpedance of the receiver 230. In these embodiments, controller 250'smatching network can be adjustable. Alternatively or additionally,controller 250 can comprise an adjustable loading impedance to stabilizethe load seen at an antenna 240 under different operating conditions. Insome embodiments, the adjustable loading impedance is controlledaccording to the charge rate of the energy storage assembly 270.

Controller 250 and/or any other component of each implantable device 200can comprise an integrated circuit comprising one or more componentsselected from the group consisting of: matching network; rectifier;DC-DC converter; regulator; bandgap reference; overvoltage protection;overcurrent protection; active charge balance circuit; analog to digitalconverter (ADC); digital to analog converter (DAC); current driver;voltage driver; digital controller; clock generator; data receiver; datademodulator; data modulator; data transmitter; electrode drivers;sensing interface analog front end; power management circuit; energystorage interface; memory register; timing circuit; and combinations ofone or more of these.

One or more receivers 230 (singly or collectively receiver 230) cancomprise one or more components, such as demodulator 231, rectifier 232and/or power converter 233 shown in FIG. 1. In some embodiments,receiver 230 can comprise a DC-DC converter such as a boost converter.Receiver 230 can comprise a data receiver, such as a data receiverincluding an envelope detector and demodulator and/or an envelopeaveraging circuit. In some embodiments, one more antennas 240 separatelyconnect to one or more receivers 230. In some embodiments, one or moreantennas 240 connect to a single receiver 230, such as via a seriesconnection or a parallel connection.

One or more implantable devices 200 can be configured to transmit a datasignal to external system 50. In some embodiments, receiver 230 isconfigured to drive one or more antennas 240 to transmit data toexternal system 50 (e.g., to an antenna 540 of an external device 500).Alternatively or additionally, implantable device 200 can be configuredto transmit a data signal by having receiver 230 adjust a load impedanceto backscatter energy, such as a backscattering of energy which can bedetected by external system 50. In some embodiments, data transmissionis accomplished by receiver 230 manipulating a signal at a tissueinterface, such as to transmit a data signal using body conduction.

In some embodiments, receiver 230 comprises a matching network, such asa matching network configured to detune to prevent oversaturation. Forexample, implantable system 20 can comprise two or more implantabledevice 200 each of which includes a receiver 230 comprising a matchingnetwork. A first implantable device 200's receiver 230's matchingnetwork can be configured to detune based on power received by thesecond implantable device 200's receiver 230.

Demodulator 231 can comprise circuitry that asynchronously recoverssignals modulated on the power signal provided by external system 50,and converts the modulated signals into digital signals. In someembodiments, demodulator 231 asynchronously recovers the modulatedsignal by comparing a dynamically generated moving average with theenvelope, outputting a high voltage when the envelope is greater thanthe moving average and a low voltage when the envelope is less than themoving average. Data can then be extracted from this resulting digitalsignal from the width and/or amplitude of the pulses in the signal,according to the encoding method used by external system 50. In someembodiments, demodulator 231 recovers a digital signal that can be usedas timing information for an implantable device 200, similar to anon-chip clock. The recovered clock signal can also be used tosynchronize an on-chip clock generator of controller 250, such asthrough the use of a frequency and/or phase locked loop (FLL or PLL).

Rectifier 232 can comprise a power signal rectifier, such as to providepower to the energy storage assembly 270 and/or controller 250. In someembodiments, rectifier 232 comprises one or more self-driven synchronousrectifier (SDSR) stages connected in charge-pump configuration, to boostthe voltage from input RF amplitude to the rectifier to a highervoltage. The boosted voltage can directly charge energy storage assembly270, or be further boosted by a DC-DC converter or boost converter. Insome embodiments, rectifier 232 can comprise diode-capacitor ladderstages instead of, or in addition to, SDSR stages. On-chip diodes, suchas Schottky diodes, or off-chip diodes can be used in one or morerectifier 232 stages. For maximum efficiency, the rectificationelements, such as diodes, can be optimized to minimize forwardconduction and/or reverse conduction losses by properly sizing thecomponents and selecting appropriate number of stages based on the inputRF voltage and load current.

Power converter 233 can comprise one or more voltage conversion elementssuch as DC-DC converters that boost or otherwise change the voltage to adesired level. In some embodiments, voltage conversion is achieved witha buck-boost converter, a boost converter, a switched capacitor, and/orcharge pumps. One or more power converters 233 can interface with energystorage assembly 270 and charge up associated energy storage componentsto desired voltages. In some embodiments, power converter 233 receivescontrol signals from controller 250, such as to configure voltages,currents, charge/discharge rates, switching frequencies, and/or otheroperating parameters of power converter 233.

One or more implantable leads 265 (singly or collectively lead 265) canbe attached to one or more housings 210, such as a lead 265 comprisingone or more functional elements 260. Lead 265 can comprise one or morefunctional elements 260 configured as a stimulation element (e.g., anelectrode configured to deliver electrical energy in monopolar orbipolar mode or an agent delivery element such as an output port fluidlyconnected to a reservoir within housing 210). Alternatively oradditionally, lead 265 can comprise one or more functional elements 260configured as a physiologic sensor (e.g., an electrode configured torecord electrical activity of tissue or other physiologic sensor asdescribed herein). Alternatively or additionally, lead 265 can compriseone or more functional elements 260 configured to transmit signalsthrough tissue to external system 50, such as through body conduction.

In some embodiments, lead 265 comprises a removable stylet configured toaid in the implantation of lead 265, such as is described in applicant'sInternational PCT Patent Application Serial Number PCT/US2016/016888,titled “Medical Apparatus including an Implantable System and anExternal System”, filed Feb. 5, 2016; the content of which isincorporated herein by reference in its entirety for all purposes. Insome embodiments, implantable system 20 comprises more than one lead265, comprising one or more functional elements 260 and attached to oneor more housings 210 of one or more implantable devices 200. In someembodiments, one or more leads 265 can be attached to a single housing210.

In some embodiments, lead 265 comprises a diameter between 1 mm and 4mm, such as a diameter between 1 mm and 2 mm. In some embodiments, lead265 comprises a length between 3 cm and 60 cm, such as a length between6 cm and 30 cm. One or more leads 265 can include between 2-64functional elements 260, such as when a lead 265 comprises between 2 and64 electrodes, such as between 4 and 32 electrodes. In some embodiments,lead 265 can comprise a paddle lead. In some embodiments, lead 265comprises a single or multi-lumen catheter, such as when an attachedimplantable device 200 is configured as an agent delivery apparatus asdescribed herein (e.g., a functional element 260 configured as acatheter comprises at least a portion of lead 265).

One or more functional elements 260 (singly or collectively functionalelement 260) can comprise one or more sensors, transducers and/or otherfunctional elements. In some embodiments, functional elements 260comprise at least one sensor and/or at least one transducer (e.g., asingle functional element 260 or multiple functional elements 260). Insome embodiments, functional element 260 comprises a functional elementconfigured to provide a therapy, such as one or more functional elements260 configured to deliver an agent to tissue (e.g., a needle orcatheter), to deliver energy to tissue and/or to otherwise affecttissue. In some embodiments, functional element 260 comprises one ormore functional elements 260 configured to record patient information,such as when functional element 260 comprises one or more sensorsconfigured to measure a patient physiologic parameter, as describedherein. In some embodiments, functional element 260 comprises one ormore sensors configured to record an implantable device 200 parameter,also as described herein.

One or more functional elements 260 can be positioned on lead 265 asshown in FIG. 1. Alternatively or additionally, one or more functionalelements 260 can be positioned on housing 210.

Functional element 260 can comprise one or more functional elementspositioned at one or more internal body locations. Functional element260 can comprise one or more functional elements positioned to interfacewith (e.g., deliver energy to and/or record a physiologic parameterfrom) spinal cord tissue, spinal canal tissue, epidural space tissue,spinal root tissue (dorsal or ventral), dorsal root ganglion, nervetissue (e.g., peripheral nerve tissue, spinal nerve tissue or cranialnerve tissue), brain tissue, ganglia (e.g., sympathetic orparasympathetic) and/or a plexus. In some embodiments, functionalelement 260 comprises one or more elements positioned proximate and/orwithin one or more tissue types and/or locations selected from the groupconsisting of: one or more nerves; one or more locations along, inand/or proximate to the spinal cord; peripheral nerves of the spinalcord including locations around the back; the tibial nerve (and/orsensory fibers that lead to the tibial nerve); the occipital nerve; thesphenopalatine ganglion; the sacral and/or pudendal nerve; brain tissue,such as the thalamus; baroreceptors in a blood vessel wall, such as inthe carotid artery; one or more muscles; the medial nerve; thehypoglossal nerve and/or one or more muscles of the tongue; cardiactissue; the anal sphincter; the dorsal root ganglion; motor nerves;muscle tissue; the spine; the vagus nerve; the renal nerve; an organ;the heart; the liver; the kidney; an artery; a vein; bone; andcombinations of one or more of these, such as to stimulate and/or recorddata from the tissue and/or location in which the functional element 260is positioned proximate to and/or within. In some embodiments, apparatus10, implantable device 200 and/or functional element 260 are configuredto stimulate spinal nerves, peripheral nerves and/or other tissue asdescribed in applicant's application International PCT Patent SerialNumber PCT/US2016/051177, titled “Apparatus for Peripheral or SpinalStimulation”, filed Sep. 9, 2016.

In some embodiments, functional element 260 comprises one or moresensors configured to record data representing a physiologic parameterof the patient. Functional element 260 can comprise one or more sensorsselected from the group consisting of: electrode; sensor configured torecord electrical activity of tissue; blood glucose sensor; gas sensor;blood gas sensor; ion concentration sensor; oxygen sensor; pressuresensor; blood pressure sensor; heart rate sensor; cardiac output sensor;inflammation sensor; neural activity sensor; neural spike sensor;muscular activity sensor; EMG sensor, bladder volume sensor, bladderpressure sensor, gastric volume sensor; peristalsis rate sensor; pHsensor; strain gauge; accelerometer; gyroscope; GPS; respiration sensor;respiration rate sensor; flow sensor; viscosity sensor; temperaturesensor; magnetic sensor; optical sensor; MEMs sensor; chemical sensor;hormone sensor; impedance sensor; tissue impedance sensor;electrode-tissue interface impedance sensor; body position sensor; bodymotion sensor; organ motion sensor; physical activity level sensor;perspiration sensor; patient hydration sensor; breath monitoring sensor;sleep monitoring sensor; food intake monitoring sensor; digestionmonitoring sensor; urine movement sensor; bowel movement sensor; tremorsensor; pain level sensor; and combinations of one or more of these.

Apparatus 10 and functional element 260 can be configured to record apatient parameter (e.g., patient physiologic and/or patient environmentparameter) selected from the group consisting of: blood glucose; bloodpressure; EKG; heart rate; cardiac output; oxygen level; pH level; pH ofblood; pH of a bodily fluids; tissue temperature; inflammation level;bacteria level; type of bacteria present; gas level; blood gas level;neural activity; neural spikes; neural spike shape; action potential;local field potential (LFP); EEG; muscular activity; skeletal muscleactivity; bladder volume; bladder pressure; gastric volume; peristalsisrate; impedance; tissue impedance; electrode-tissue interface impedance;physical activity level; pain level; body position; body motion; organmotion; respiration rate; respiration level; perspiration rate; sleeplevel; sleep cycle; digestion state; digestion level; urine production;urine flow; bowel movement; tremor; ion concentration; chemicalconcentration; hormone level; viscosity of a bodily fluid; patienthydration level; and combinations of one or more of these.

In some embodiments, functional element 260 comprises one or moresensors configured to record data representing a parameter ofimplantable device 200. In these embodiments, functional element 260 cancomprise one or more sensors selected from the group consisting of: anenergy sensor; a voltage sensor; a current sensor; a temperature sensor(e.g., a temperature of one or more components of implantable device200); a contamination detector (e.g., to detect undesired material thathas passed through housing 210); an antenna matching and/or mismatchingassessment sensor; power transfer sensor; link gain sensor; power usesensor; energy level sensor; energy charge rate sensor; energy dischargerate sensor; impedance sensor; load impedance sensor; instantaneouspower usage sensor; average power usage sensor; bit error rate sensor;signal integrity sensor; and combinations of one or more of these.Apparatus 10 can be configured to analyze (e.g., via implantablecontroller 250, programmer 550 and/or diagnostic assembly 91 describedherebelow) the data recorded by functional element 260 to assess one ormore of: power transfer; link gain; power use; energy within energystorage assembly 270; performance of energy storage assembly 270;expected life of energy storage assembly 270; discharge rate of energystorage assembly 270; ripple or other variations of energy storageassembly 270; matching of antenna 240 and 540; communication error ratebetween implantable device 200 and external device 500; integrity oftransmission between implantable device 200 and external device 500; andcombinations of one or more of these. A functional element 260 can beconfigured to record temperature, such as when apparatus 10 isconfigured to deactivate or otherwise modify the performance of animplantable device 500 when the recorded temperature exceeds athreshold.

In some embodiments, one or more functional elements 260 comprise atransducer configured to deliver energy to tissue, such as to treat painand/or to otherwise stimulate or affect tissue. In some embodiments,functional element 260 comprises a stimulation element, such as one ormore transducers selected from the group consisting of: an electrode; anenergy delivery element such as an electrical energy delivery element, alight energy delivery element, a laser light energy delivery element, asound energy delivery element, a subsonic sound energy delivery elementand/or an ultrasonic sound delivery element; an electromagnetic fieldgenerating element; a magnetic field generating element; a mechanicaltransducer (e.g., delivering mechanical energy to tissue); a tissuemanipulating element; a heat generating element; a cooling (e.g.,cryogenic or otherwise heat extracting energy) element; an agentdelivery element such as a pharmaceutical drug delivery element; andcombinations of one or more of these.

In some embodiments, one or more functional elements 260 comprises adrug or other agent delivery element, such as a needle, port,iontophoretic element, catheter, or other agent delivering element thatcan be connected to a reservoir of agent positioned within housing 210(e.g., reservoir 225 described herebelow). In some embodiments, one ormore functional elements 260 comprise a drug eluting element configuredto improve biocompatibility of implantable system 20.

In some embodiments, one or more functional elements 260 comprise one ormore electrodes configured to deliver energy to tissue and/or to sense apatient parameter (e.g., electrical activity of tissue or other patientphysiologic parameter). In these embodiments, one or more functionalelements 260 can comprise one or more electrodes selected from the groupconsisting of: microelectrode; cuff electrode; array of electrodes;linear array of electrodes; circular array of electrodes; paddle-shapedarray of electrodes; bifurcated electrodes; and combinations of one ormore of these.

In some embodiments, apparatus 10 and functional element 260 areconfigured to both record one or more patient parameters, and also toperform a medical therapy (e.g., stimulation of tissue with energyand/or an agent). In these embodiments, the medical therapy can beperformed in a closed-loop fashion, such as when energy and/or agentdelivery is modified based on the measured one or more patientphysiologic parameters.

In some embodiments, one or more functional elements 260 comprise anagent delivery element, such as a fluid delivery element (e.g., acatheter, a porous membrane, an iontophoretic element or a needle) influid communication with a reservoir of the agent positioned withinhousing 210, such as reservoir 225 described herebelow.

In some embodiments, apparatus 10 comprises tool 60. Tool 60 cancomprise a data logging and/or analysis tool configured to receive datafrom external system 50 or implantable system 20, such as datacomprising: diagnostic information recorded by external system 50 and/orimplantable system 20; therapeutic information recorded by externalsystem 50 and/or implantable system 20; patient information (e.g.,patient physiologic information) recorded by implantable system 20;patient environment information recorded by implantable system 20; andcombinations of one or more of these. Tool 60 can be configured toreceive data from wired or wireless (e.g., Bluetooth) means. Tool 60 cancomprise a tool selected from the group consisting of: a data loggingand/or storage tool; a data analysis tool; a network such as a LAN orthe Internet; a cell phone; and combinations of one or more of these.

In some embodiments, tool 60 comprises a battery charging assembly, suchas an assembly configured to recharge one or more power supplies 570comprising a rechargeable battery or capacitor.

In some embodiments, tool 60 comprises an implantation tool, such as anintroducer or other implantation tool constructed and arranged to aid inthe implantation of housing 210, implantable antenna 240, lead 265and/or one or more functional elements 260.

In some embodiments, lead 265 comprises a paddle lead or otherstimulating lead and tool 60 comprises an introducer (e.g., a needle oran extended-width introducer) configured to deliver at least a distalportion of lead 265 into an epidural space of a patient. Tool 60 cancomprise an introducer comprising a Tuohy needle, such as a Tuohy needleof 12 gauge or smaller. Tool 60 can comprise a handle for manipulatinglead 265. Tool 60 can be configured to place lead 265 at an entry pointabove the lumbar spinal column (e.g., between L1 and L2 vertebrae). Tool60 can include extension tubing used to insert lead 265. Tool 60 canfurther comprise a tool configured to anchor lead 265, such as when tool60 comprises sutures, clips, other anchoring elements and/or an anchorsecuring tool (e.g., a needle or a stapling device), such as to securelead 265 in subcutaneous tissue. Lead 265 and/or tool 60 can compriseextension tubing used to place lead 265, such as extension tubing thatremains in place after removal of an introducer of tool 60. Tool 60 canbe configured to place lead 265 against the dura of the spinal cord ofthe patient.

In some embodiments, tool 60 and/or lead 265 are constructed andarranged to implant lead 265 to stimulate one or more multifidus (MF)muscle fascicles, such as at least three sets of multifidus musclefascicles. Lead 265 can be secured to a vertebra (e.g., on thetransverse process, lamina or vertebral body). Lead 265 can placed viatool 60 such that one or more functional elements 260 (e.g., electrodes)are positioned within the multifidus muscle structures. One or morefunctional elements 260 can be positioned to deliver electrical energyand/or to otherwise stimulate tissue selected from the group consistingof: muscle motor point(s) or the deep fibers of lumbar multifidus;quadratus lumborum; the erector spinae; psoas major; transverseabdominis; connective tissue such as the annulus or facet capsule;ligaments coupling bony structures of the spine; and combinations of oneor more of these. Functional elements 260 can be positioned to:depolarize, hyperpolarize and/or block innervated sections of the musclethat will then propagate an activating and/or inhibiting stimulus alongthe nerve fibers recruiting muscle tissue remote from the site ofstimulation and/or modulate nerve activity (including inhibiting nerveconduction, improving nerve conduction and/or improving muscleactivity). In some embodiments, functional elements 260 are positionedto cause transvascular stimulation (e.g., transvascular stimulation fromarteries and/or veins in a leg or arm). In some embodiments, functionalelements 260 are positioned to stimulate nerve tissue selected from thegroup consisting of: dorsal ramus nerve; medial branch of dorsal ramusnerve; nervous tissue associated with multifidus muscle; andcombinations of one or more of these. In some embodiments, functionalelements 260 are configured to deliver stimulation energy to contractthe multifidus muscle. In some embodiments, functional elements 260 areconfigured to stimulate tissue by providing episodic electricalstimulation. In some embodiments, apparatus 10 comprises a tool 60configured to diagnose a defect in spinal muscle or the motor controlsystem. In some embodiments, apparatus 10 comprises a tool 60 configuredto test function of the multifidus muscle, such as when tool comprisesan MRI; ultrasound imager; electromyogram; tissue biopsy device; and/ora device configured to test displacement as a function of load for aspine.

In some embodiments, two or more external system 50 components areconnected by a connecting filament, such as is described hereabove.Alternatively or additionally, two or more implantable system 20components are connected by a conduit, such as a connecting filament asdescribed herein. Alternatively or additionally, two more externalsystem 50 components and/or two or more implantable system 20 componentstransmit information and/or power via a wireless transmitter (e.g., anRF transmitter), magnetic coupling, capacitive coupling and/or otherwireless transmission means,

Apparatus 10 can include one or more devices, such as patient attachmentdevice 70 shown in FIG. 1, that is used to attach one or more portionsof external system 50 to a location on or proximate the patient. In someembodiments, patient attachment device 70 is constructed and arranged asdescribed in applicant's International PCT Patent Application SerialNumber PCT/US2015/036821, titled “Method and Apparatus forNeuromodulation Treatments of Pain and Other Conditions”, filed Jun. 19,2015, the content of which is incorporated herein by reference in itsentirety for all purposes.

Patient attachment device 70 can comprise one or more elementsconfigured to attach one or more external devices 500 at one or morelocations on or proximate the patient's skin, that are relatively closeto one or more implantable devices 200 that have been implanted in thepatient. Patient attachment device 70 can comprise a component selectedfrom the group consisting of: belt; belt with pockets; belt withadhesive, adhesive; strap; strap with pockets; strap with adhesiveshoulder strap; shoulder band; shirt; shirt with pockets; clothing;clothing with pockets; epidural electronics packaging; clip; bracelet;wrist band; wrist watch; anklet; ankle bracelet; knee strap; knee band;thigh strap; thigh band; necklace; hat; headband; collar; glasses;goggles; earpiece; behind-the-earpiece; and combinations of one or moreof these. In some embodiments, patient attachment device 70 comprises abelt configured to surround at least one antenna 540 (e.g., at least oneantenna 540 mounted to or otherwise positioned on a printed circuitboard such as a flexible printed circuit board). Patient attachmentdevice 70 can include one or more pockets, such as one or more pocketsconfigured to collectively surround one or more of: external device 500;one or more antennas 540; power supply 570; programmer 550; andcombinations of one or more of these. In some embodiments, patientattachment device 70 comprises multiple pockets, such as to allowrepositioning of an external antenna 540, programmer 550, externaltransmitter 530 and/or external power supply 570 to various differentlocations, such as to improve transmission of power and/or data to oneor more implantable devices 200 and/or improve patient comfort. In someembodiments, one or more antennas 540, power supplies 570, and/ortransmitters 530 are connected through flexible cables positioned inpatient attachment device 70. In some embodiments, the flexible cablesare small coax cables that can accommodate the power levels andfrequencies of the carried signals. In some embodiments, the one or moreantennas 540 are connected to one or more additional components ofexternal device 500 through a single cable with a local power splittingcomponent and/or active matching element that adjusts signal power toeach of the one or more antennas 540.

Apparatus 10 can comprise a device configured to operate (e.g.,temporarily operate) one or more implantable devices 200, such astrialing interface 80 shown in FIG. 1. Trialing interface 80 can beconfigured to deliver power to an implantable device 200, deliver datato an implantable device 200, and/or receive data from an implantabledevice 200. Trialing interface 80 can be configured to interface withone or more implantable devices 200 during an implantation procedure inwhich one or more implantable device 200 are implanted in a patient(e.g., a sterile clinical procedure). Trialing interface 80 can beconfigured to be sterilized one or more times. Trialing interface 80 cancomprise one or more antennas, such as an antenna similar to antenna 540of an external device 500. Trial interface 80 can comprise atransmitter, such as a transmitter similar to transmitter 530 ofexternal device 500, and a power supply, such as a power supply similarto power supply 570 of external device 500. In some embodiments,trialing interface is of similar construction and arrangement to thetrialing interface described in applicant's International PCT PatentApplication Serial Number PCT/US2015/036821, titled “Method andApparatus for Neuromodulation Treatments of Pain and Other Conditions”,filed Jun. 19, 2015, the content of which is incorporated herein byreference in its entirety for all purposes. In some embodiments,trialing interface 80 includes a housing to be positioned proximate atleast a portion of implantable device 200, such as a housing thatsurrounds an antenna and a transmitter that is configured to operativelycouple to (e.g., transmit power and/or data to) one or more antennas 240of one or more implantable devices 200.

In some embodiments, one or more implantable devices 200 of implantablesystem 20 can comprise an implantable transmitter configured to transmitdata, such as to transmit data (e.g., stimulation information, patientphysiologic information, patient environment information, implantabledevice 200 performance and/or configuration information, and the like)to one or more external devices 500. In these embodiments, receiver 230can be configured as both a receiver and a transmitter. One or moreimplantable devices 200 can be configured to transmit data by sending asignal to (i.e., “driving”) one or more antennas 240 or another antennaof implantable device 200. An implantable device 200 can be configuredto transmit data using one or more of: load modulation; a signalcarrier; and/or body conduction. An implantable device 200 can beconfigured to adjust the transmission, such as to adjust a datatransmission parameter selected from the group consisting of: data rate;pulse width; duration of carrier signal; amplitude of carrier signal;frequency of carrier signal; configurable load; and combinations of oneor more of these.

In some embodiments, apparatus 10 comprises a diagnostic assembly,diagnostic assembly 91 shown in FIG. 1. In some embodiments, programmer550 and/or implantable controller 250 comprise all or a portion ofdiagnostic assembly 91. Diagnostic assembly 91 can be configured toassess, monitor, determine and/or otherwise analyze patient informationand/or implantable device 200 information, such as when one or morefunctional elements 260 and/or 560 are configured as a sensor configuredto record patient information (e.g., patient physiologic informationand/or patient environment information) and/or apparatus 10 information(e.g., implantable device 200 information) as described herein.Diagnostic assembly 91 can be configured to analyze communication and/orthe power link between an implantable device 200 and an external device500. In some embodiments, such a communication link analysis can beperformed by measuring bit error rate (BER) of a known data streamduring communication signal transmission (also referred to as“communication link”) measurement phase (e.g., such as during acalibration procedure). The BER can be tracked by the implant controller250 or programmer 550, such as to monitor and keep track of any trendsin the link. This trend can be used to adjust the link and/or providefeedback to an operator of apparatus 10 (e.g., the patient), in case thelink cannot be automatically adjusted to compensate for a negative trend(e.g., such that the operator can perform physical re-adjustment of theexternal system 50). Alternatively or additionally, a power linkanalysis can be performed by monitoring charge/discharge rate of theimplanted energy storage assembly 270. Similar to the communicationlink, the power link status and/or trending can be monitored andrecorded for link adjustment and/or feedback purposes. Diagnosticassembly 91 can be configured to analyze a result of stimulation energydelivered by implantable device 200, such as when a functional element260 comprises an electrode to record electrical activity of tissue(e.g., in addition to delivering electrical energy to stimulate tissue).A functional element 260 and/or 560 can comprise a sensor configured torecord neural activity and/or muscular activity, and the diagnosticassembly configured to analyze the recorded sensor data. In someembodiments, diagnostic assembly 91 can be configured to analyzeimpedance, such as when a functional element 260 and/or 560 comprises asensor configured to record data related to impedance, such as whenimplantable device 200 performs a frequency sweep, performs an impulseresponse and/or compares voltage and current of a stimulation waveform.In some embodiments, diagnostic assembly 91 is configured to assess theimpedance of one or more implantable antennas 240 and/or one or moreexternal antennas 540. In these embodiments, impedance can be assessedby performing a function selected from the group consisting of:performing a frequency sweep; performing an impulse response; comparingvoltage and current of a waveform; and combinations of one or more ofthese.

In some embodiments, diagnostic assembly 91 is configured to test orotherwise assess the link between one or more implantable antennas 240and one or more external antennas 540 (e.g., during a procedure in whichone or more implantable devices 200 are implanted in a patient). Inthese embodiments, diagnostic assembly 91 can be configured to perform atest prior to anchoring housing 210 to tissue (e.g., prior to initial orfinal suturing into tissue such as the fascia layer). For example, lead265 can be implanted at a location to stimulate target tissue (e.g., oneor more nerves identified to treat pain or another patient condition).Prior to suturing housing 210 in its permanent location, diagnosticassembly 91 can be configured to confirm that one or more externalantenna 540 transmission links to one or more implantable antennas 240are above an efficiency threshold, for example such that sufficientpower will be received by the one or more implantable devices 200.Additionally, the procedure can be performed to optimize or otherwiseimprove the position of the one or more implantable devices 200 to beimplanted and subsequently secured to tissue.

In these link testing embodiments, diagnostic assembly 91 can comprise ahandheld assembly (e.g., a sterile assembly comprising a wand or otherhandheld housing). Diagnostic assembly 91 can be configured to send asimple signal to one or more implantable devices 200 (e.g., a diagnosticassembly 91 with similar power and/or data transmission capabilities asan external device 500). Each implantable device 200 can respond (e.g.,via data sent via an implantable antenna 240 or other transmitter) withinformation related to the quality of the transmission link (e.g.,information about the power received by the one or more implantabledevices 200). Diagnostic assembly 91 could provide a user interface(e.g., a speaker, a text screen and/or a video display) that providesquality or other information (go/no go information, digital or otherdiscrete level information, and/or analog information). Diagnosticassembly 91 could be further configured to provide informationconfirming detection of one or more implantable devices 200, status ofone or more implantable devices 200 (e.g., parameter level and/or faultdetection status), and/or self-diagnostic status (i.e., diagnosticassembly 91 status).

Each implantable device 200 can be configured to specifically identifyand/or specifically reply to diagnostic assembly 91 (e.g., in adifferent form than communications with an external device 500). Eachimplantable device 200 can be configured to provide information relatedto one or more of: the charge and/or discharge rate of energy storageassembly 270 (e.g., the charge and/or discharge rate of a capacitor orbattery of energy storage assembly 270); or the frequency of avoltage-controlled oscillator that is driven by an unregulated voltageof power converter 233. Diagnostic assembly 91 can be configured toperform numerous performance tests (e.g., of one or more implantabledevices 200 or implantation locations for one or more implantabledevices 200), prior to completion of the implantation procedure (e.g.,prior to closing one or more incisions).

In some embodiments, apparatus 10 is configured to provide a therapy bydelivering stimulation energy to tissue, such as electrical energydelivered to tissue by one or more functional elements 260 comprisingone or more electrodes. Alternatively or additionally, apparatus 10 canbe configured as an agent-delivery apparatus (e.g., a pharmaceutical orother agent delivery apparatus). In some embodiments, apparatus 10comprises one or more reservoirs for storing the agent, such asreservoir 525 of external device 500 and/or reservoir 225 of implantabledevice 200, each shown in FIG. 1. Reservoirs 525 and/or 225 can befluidly connected to one or more functional elements 560 and/or 260,respectively (e.g., via one or more tubes). Reservoirs 525 and/or 225can comprise one or more chambers (e.g., independent chambers configuredto separately contain incompatible drugs or otherwise prevent undesiredmultiple drug interactions). Reservoirs 525 and/or 225 can comprise avolume (e.g., a volume to store one or more agents) between 0.1 ml and50 ml, such as between 0.1 ml and 3.0 ml, or between 0.1 ml and 1.0 ml.Reservoirs 525 and/or 225 can comprise pressurized reservoirs orotherwise comprise a fluid pumping mechanism (e.g., a peristalticmechanism, syringe pump or other fluid pump). Reservoirs 525 and/or 225and can comprise refillable reservoirs (e.g., when reservoir 225 of animplantable device 200 comprises a valved opening such as a siliconeseptum or a mechanical valve, either accessible via a needle forrefilling). The fluidly attached functional elements 560 and/or 260 cancomprise a fluid delivery element selected from the group consisting of:a catheter; a porous membrane; an iontophoretic element; a needle; orcombinations of one or more of these. Delivered and/or stored (e.g., ina reservoir) agents can comprise an agent selected from the groupconsisting of: an analgesic agent such as morphine, fentanyl, lidocaineor other agent delivered to treat pain; a chemotherapeutic agent such asa chemotherapeutic agent delivered systemically (e.g., throughout theblood system of the patient) and/or to a location in or proximate anorgan such as the liver or brain to treat cancer; an antibioticconfigured to treat or prevent an infection; a hormone such as a hormonedelivered intravenously in hormonal therapy; heart medications such asnitroglycerin, a beta blocker or a blood pressure lowering medication; acarbohydrate such as glucose or dextrose delivered to treat a low bloodsugar condition; insulin such as to treat a high blood sugar condition;a diabetic medication; a neurological medication; an epilepsymedication; and combinations of one or more of these. In someembodiments, apparatus 10 comprises the one or more agents stored inreservoir 225 and/or 525. In some embodiments, apparatus 10 isconstructed and arranged to deliver the agent (e.g., via acatheter-based functional element 560 and/or 260) to a patient locationselected from the group consisting of: a vessel; a blood vessel; a vein;an artery; heart; brain; liver; spine; epidural space; intrathecalspace; subcutaneous tissue; bone; intraperitoneal space,intraventricular space, and combinations of one or more of these.

In some embodiments, an external device 500 is attached to the patientvia a patient attachment device 70 comprising a wrist band, wrist watch,leg band, ankle band or other band configured to position an externaldevice 500 about a limb of the patient (i.e., arm or leg of thepatient). In these embodiments, one or more implantable devices 200 areimplanted under the skin proximate the intended (limb) location ofexternal device 500 and patient attachment device 70. Apparatus 10 canbe configured such that external device 500 comprises one or moreantennas 540; one or more implantable devices 200 each comprise one ormore antennas 240; and each implantable device 200 one or more antennas240 receive power and/or data from the one or more antennas 540 of thelimb-attached external device 500. The limb-attached external device 500can comprise one or more reservoirs 525 described hereabove and/or oneor more functional elements 560 configured as agent delivery elementsand/or sensors. The one or more implantable devices 200 can comprise oneor more reservoirs 225 described hereabove and/or one or more functionalelements 260 configured as agent delivery elements and/or sensors.

In some embodiments, apparatus 10 comprises an agent delivery apparatusand agent is delivered into the patient (e.g., into a blood vessel,muscle or subcutaneous tissue) by an external device 500 functionalelement 560 (e.g., a needle) based on signals recorded by an implantabledevice 200 functional element 260 (e.g., a sensor). Alternatively oradditionally, agent can be delivered into the patient (e.g., into ablood vessel, muscle or subcutaneous tissue) by an implantable device500 functional element 260 (e.g., a needle, catheter, porous membrane oriontophoretic delivery element). The amount of agent delivered byfunctional element 260 can be based on signals recorded by animplantable device 200 functional element 260 (e.g., a sensor) and/or anexternal device 500 functional element 560 (e.g., a sensor). Externaldevice 500 can provide power to one or more implantable devices 200and/or it can send data (e.g., sensor data from a functional element560) to implantable device 500, such as to control agent delivery byimplantable device 500.

Apparatus 10 can be configured to prevent an electromagnetic field(e.g., an electromagnetic field produced by one or more devices notincluded in apparatus 10 and/or other present in the patientenvironment) from adversely affecting and/or otherwise affecting thepatient treatment and/or patient information recording (e.g., patienttissue stimulation and/or patient physiologic information gathering)performed by apparatus 10. Electromagnetic fields from one or moreapparatus 10 devices and/or otherwise present in the patient environmentcan potentially interfere with apparatus 10. The architecture of thewireless signal transmissions of apparatus 10 can be configured toinclude certain unique and/or identifiable patterns in the signalstransmitted by apparatus 10 to confirm (upon receipt) that the signaloriginated from a component of apparatus 10. Alternatively oradditionally, the stimulation signal produced by an implantable device200 can be created independent from a power signal received from anexternal device 500, so that any electromagnetic interference in thewireless link does not affect generation and delivery of the stimulationsignal. In some embodiments, each implantable device 200 and/or externaldevice 500 includes unique identification codes that are required to betransmitted prior to any changes in stimulation or other implantabledevice 200 configuration, ensuring correct operation in the presence ofinterference. Alternatively or additionally, the communication link canincorporate handshaking protocols, confirmation protocols, dataencryption and/or scrambling, coding and other security measures toensure that interfering signals do not adversely affect the implantablesystem 20 performance (e.g., stimulation). In some embodiments, externalsystem 50 and/or implantable system 20 can incorporate electromagneticabsorptive and/or reflective materials to minimize external interferencefrom other sources and/or minimize the probability of apparatus 10interfering with other systems. Alternatively or additionally, apparatus10 can incorporate error detection and protocols for entering an alarmstate (e.g., and shutting down normal operation) and/or otherwiseensuring safe operation.

In some embodiments, implantable system 20 of apparatus 10 is configuredto perform magnetic field modulation, such as targeted magnetic fieldneuromodulation (TMFN), electro-magnetic field neuromodulation, such astargeted electro-magnetic field neuromodulation (TEMFN), transcutaneousmagnetic field stimulation (TMS), or any combination of these. Eachimplantable device 200, via one or more of its functional elements 260(e.g., electrodes) can be configured to provide localized (e.g.,targeted) magnetic and/or electrical stimulation. Combined electricalfield stimulation and magnetic field stimulation can be applied by usingsuperposition, and can reduce the overall energy requirement. In someembodiments, implantable apparatus 10 comprises one or more functionalelements 260 comprising a magnetic field generating transducer (e.g.,microcoils or cuff electrodes positioned to partially surround orotherwise be proximate to one or more target nerves). Functionalelements 260 comprising microcoils can be aligned with nerves tominimize affecting non-targeted tissue (e.g., to avoid one or moreundesired effects to non-target tissue surrounding or otherwiseproximate the target tissue). In some embodiments, the target tissuecomprises DRG tissue, and the non-target tissue comprises ventral roottissue (e.g., when the stimulation energy is below a threshold thatwould result in ventral root tissue stimulation).

In some embodiments, external system 50 of apparatus 10 is configured toprovide mechanically adjustable alignment of one or more externalantennas 540 alignment. Link gain between one or more external antennas540 and one or more implantable antennas 240 can degrade over time dueto physical misalignment of the antennas, relative orientation changebetween antennas and/or relative angular misalignment between antennas.In order to compensate for misaligned antennas, electrical beam steeringcan be included in apparatus 10. Antennas comprising a multi-feedantenna structure and/or an array of antennas can be incorporated (e.g.,into external antenna 540, implantable antenna 240 or both) forelectrical beam steering. Alternatively or additionally, mechanicalantenna steering can be implemented to physically realign one or moreexternal antennas 540 with one or more implanted antennas 240 (or viceversa). A substrate of an implantable antenna 240 and/or an externalantenna 540 can be flexible and/or rigid (e.g., a substrate comprisingpolyamide, polyimide, liquid crystal polymer (LCP), Rogers, FR4, or asimilar material). One or more antennas 540 can be connected toelectronics (e.g., a transmitter, receiver or transceiver) using aflexible waveguide or cable (e.g., 50 Ohm 0.047″ coaxial cable designedto provide patient comfort) and/or a flexible PCB substrate transmissionline. Mechanical or physical realignment of antennas 240 and/or 540 canbe accomplished using one or more of: use of motorized positioners, suchas a mechanism including one or more small pulleys and/or tensionersused to translate one or more antennas 240 and/or 540 about one or moreaxes; an actuator (e.g., a piezoelectric actuator) with directionalgears configured to translate one or more antennas 240 and/or 540 aboutone or more axes; a micro-pump with fluid reservoir (e.g., liquid or gasreservoir) configured to hydraulically and/or pneumatically translateone or more antennas 240 and/or 540 about one or more axes, such as bycreating a local pressure difference. In some embodiments, a micro-pumpwith fluid reservoir can be used to move one or more antennas 240 and/or540, such as to move an external antenna 540 away from tissue to reducespecific absorption rate (SAR). In these embodiments, external antenna540 can be positioned in mechanical contact with an expandable reservoir(e.g., a balloon) positioned between external antenna 540 and tissue.The reservoir can be inflated or deflated to control separation distanceof the external antenna 540 from the patient's skin surface. In someembodiments, apparatus 10 comprises one or more algorithm positioningalgorithms, beam steering functionality and/or mechanical antennasteering as described in applicant's U.S. patent application Ser. No.14/975,358, titled “Method and Apparatus for Minimally InvasiveImplantable Modulators”, filed Dec. 18, 2015, or International PCTPatent Application Serial Number PCT/US2016/016888, titled “MedicalApparatus including an Implantable System and an External System”, filedFeb. 5, 2016, the content of each of which is incorporated herein in itsentirety for all purposes.

In some embodiments, implantable system 20 of apparatus 10 is configuredto provide paresthesia-reduced (e.g., paresthesia-free) high frequencypain management and rehabilitation therapy (e.g., via delivery of astimulation signal above 600 Hz or 1 kHz, or other stimulation signalresulting in minimal paresthesia). Apparatus 10 can be configured toprovide both low frequency (e.g., <1 kHz) stimulation and high frequencystimulation, such as when providing low frequency stimulation to elicitfeedback from a patient during intraoperative or other (e.g.,post-implantation) stimulation configuration. For example, trialinginterface 80 can be used during an intra-operative titration ofstimulation configuration using low frequency stimulation (e.g., toposition and/or confirm position of one or more functional elements 260,such as to confirm sufficient proximity to target tissue to bestimulated and/or sufficient distance from non-target tissue not to bestimulated). In some embodiments, high frequency stimulation isdelivered to reduce pain over extended periods of time, and lowfrequency stimulation is used in these intraoperative and/orpost-implantation titration or other stimulation configurationprocedures. Intentional elicitation of paresthesia (e.g., via lowfrequency stimulation and/or high frequency stimulation) is beneficialduring functional element 260 (e.g., electrode) implantation because apatient can provide feedback to the implanting clinician to ensure thatthe functional elements 260 are positioned close to the targetneuromodulation or energy delivery site. This implantationposition-optimizing procedure can advantageously reduce the requiredstimulation energy due to functional elements 260 being closer to targettissue, since a minimum threshold for efficacious stimulation amplitudeis proportional to the proximity of functional elements 260 to targettissue (e.g., target nerves). The patient can inform the clinician ofthe sensation of paresthesia coverage, and the clinician can adjustfunctional element 260 position to optimize functional element 260location for efficacious treatment while minimizing unintentionalstimulation of non-target tissue (e.g., motor nerves or other nerveswhich are not causing the patient's pain). These paresthesia-inducingtechniques (e.g., using low frequency stimulation and/or high frequencystimulation) can be used during or after implantation of one or moreimplantable devices 200.

In some embodiments, apparatus 10 is configured to deliver low frequencystimulation energy (e.g., electrical energy comprising a low frequencysignal) to stimulate motor nerves, such as to improve tone andstructural support (e.g., physical therapy). In these embodiments,apparatus 10 can be further configured to provide high frequencystimulation, such as to treat pain (e.g., suppress and/or control pain).The combined effect can be used not only for pain management but alsomuscle strengthening and gradual healing of supportive structures.Alternatively or additionally, as described herein, apparatus 10 can beconfigured to deliver low frequency stimulation energy (e.g., electricalenergy) to induce paresthesia, which can also be accompanied by thedelivery of high frequency stimulation (e.g., to suppress and/or controlpain). In some embodiments, apparatus 10 is configured to deliver lowfrequency stimulation (e.g., electrical energy comprising a lowfrequency signal) and burst stimulation, delivered simultaneously orsequentially. The low frequency stimulation and the burst stimulationcan be delivered on similar and/or dissimilar functional elements 260(e.g., similar or dissimilar electrode-based functional elements 260).

As described herein, apparatus 10 can be configured for treatingnumerous disease and disorders, such as when apparatus 10 is configuredto deliver electrical or other stimulation energy to treat pain (e.g.,by delivering electrical or other energy to the spine or other neurallocation). Apparatus 10 can be configured to stimulate tissue withvarious stimulation waveforms, such as those described in applicant'sU.S. Provisional Patent Application Ser. No. 62/417,907, titled“Apparatus with Enhanced Stimulation Waveforms”, filed Nov. 4, 2016, thecontent of which is incorporated herein by reference in its entirety forall purposes.

Apparatus 10 can be configured to treat neuropathy, neuralgia and/orother nerve pain that is related to: surgery; trauma; infection (e.g., aherpetic infection); and/or diabetes (e.g., diabetic neuropathy). One ormore functional elements 260 can be configured to deliver stimulationenergy (e.g., electrical energy, magnetic energy, light energy, thermalenergy, sound energy, and/or chemical energy (e.g., energy from a drugor reagent) to nerve tissue such as tissue of the central nervous systemand/or peripheral nervous system. One or more leads 265 (each comprisingone or more functional elements 260) can be implanted in and/orproximate the spinal cord, the groin and/or a joint such as the hip. Forexample, apparatus 10 can be configured to treat one or more of:post-surgical neuralgia (e.g., following hernia repair such as a herniarepair including an implanted mesh); headache (e.g., due to occipitalneuralgia); post-herpetic neuralgia; chronic pelvic and/or hip pain;knee pain; and combinations of one or more of these.

To treat pain related to hernia or hernia repair, one or more functionalelements 260 (e.g., on a lead 265 and/or on a housing 210) can bepositioned to stimulate tissue of the peripheral nervous system and/orthe central nervous system. In some embodiments, one or more functionalelements 260 are positioned to stimulate the cutaneous branch of theilioinguinal, inguinal and/or genital branch of the genitofemoralnerves. In some embodiments, one or more functional elements 260 arepositioned to stimulate corresponding branches of spinal nervescorrelating to one or more dermatomes related to pain associated with atleast one of hernia or hernia repair.

Hernia or hernia repair can lead to: inguinal pain; ilioinguinalneuralgia; post-traumatic neuropathic pain; ilioinguinal nerveentrapment; neuropathic pain of ilioinguinal origin; post-surgicalinguinal pain; genitofemoral pain; genitofemoral neuralgia;genitofemoral nerve entrapment; neuropathic pain of genitofemoralorigin; post-surgical genitofemoral pain; iliohypogastric pain;iliohypogastric neuralgia; iliohypogastric nerve entrapment; neuropathicpain of iliohypogastric origin; post-surgical iliohypogastric pain;testicular pain; scrotal pain; penis pain; groin pain; thigh pain; analpain; rectal pain; perineal pain; abdominal adhesions; pelvic adhesions;scar pain; diffuse polyneuropathy; and combinations of one or more ofthese.

The apparatus of the present inventive concepts can be configured tostimulate the ilioinguinal nerve, genitofemoral nerve and/oriliohypogastric nerves, such as to ameliorate pain following herniarepair. One or more leads 265 (e.g., one or more leads 265 comprisingone or more electrode-based or otherwise stimulation-based functionalelements 260) can be inserted over the inguinal region (which mayinclude the inguinal ring) to stimulate any or all three of these nerves(e.g., in a unilateral or bilateral fashion). Both the ilioinguinal andgenital branch of the genitofemoral nerves pass through the inguinalring. The anterior cutaneous iliohypogastric and femoral branch of thegenitofemoral nerve can be stimulated at one or more locations proximatebut rostral (iliohypogastric) or lateral (genitofemoral) to the inguinalring. Leads 265 can comprise one or more functional elements 260comprising cylindrical, paddle, cuff and/or hemi-cuff electrodes(electrodes placed surgically near and/or around these nerves). Thenerves can be localized via ultrasound or other imaging modalities.Contrast can be used to image the vessels nearby (e.g., the testicularand/or ovarian vein and/or artery). The genital branch of thegenitofemoral nerve can be stimulated in a transvascular manner throughthe testicular vein and/or artery. The genitofemoral and/or theilioinguinal nerves can also be stimulated (e.g., transvascularlystimulated) through the femoral vein and/or artery, or via thesuperficial or deep external pudendal vein and/or artery, and/or via thesuperficial epigastric vein and/or artery.

The painful areas innervated by the ilioinguinal nerve, genitofemoralnerve and/or iliohypogastric nerves, can also be treated via spinal cordstimulation provided by apparatus 10 in the L1-L5 region of the spinalcord. In some embodiments, direct stimulation of the L1-L2 dorsal rootganglia is provided in a similar treatment. Leads 265 (e.g.,percutaneous or paddle) including stimulation-based functional elements260 can be placed over the dorsal columns, over the dorsal roots and/orin the dorsal root entry zone, in a unilateral, bilateral and/or midlinefashion.

To treat occipital neuralgia, also known as C2 neuralgia, one or morefunctional elements 260 can be positioned to stimulate peripheral nervetissue to reduce pain. Occipital neuralgia is a medical conditioncharacterized by chronic pain in the upper neck, back of the head and/orbehind the eyes (areas corresponding to the locations of the lesser andgreater occipital nerves). In some embodiments, one or more leads 265,each comprising one or more functional elements 260, can be implantedtransversely, either unilaterally or bilaterally, at the level of theappropriate target cervical nerve (C1, C2, etc.). The C1, 2, 3 cervicalroots include the greater occipital nerve which originates primarilyfrom C2, and the lesser occipital nerves. Relevant trigeminal branchesinclude both the supraorbital and supratrochlear nerves from V1, theinfraorbital branches from V2, and the superficial temporal nerves fromV3. A partial convergence of these two systems occurs at theTrigemino-Cervical Complex (TCC). In some embodiments, one or morefunctional elements 260 are positioned to stimulate the trigeminaland/or occipital nerves. One or more leads 265 can be anchored to thefascia proximate the tissue to be stimulated.

To treat post-herpetic neuralgia (e.g., neuralgia associated withshingles), one or more functional elements 260 can be positioned tostimulate corresponding branches of the spinal nerves correlating to oneor more dermatomes related to the patient's shingles.

In some embodiments, apparatus 10 is configured to treat pelvic, bladderand/or bowel disorders, such as by stimulating sacral, pudendal and/ortibial nerves. In some embodiments, apparatus 10 is configured to treatpelvic pain by stimulating the tibial nerve.

Apparatus 10 can be configured to treat a bladder, bowel or otherdysfunction selected from the group consisting of: overactive bladder;urinary urgency; urinary frequency; urinary urgency frequency; urinaryurge incontinence; urinary stress incontinence; urge incontinence;stress incontinence; non-obstructive urinary retention; female sexualdysfunction; fecal incontinence; constipation; diarrhea; irritable bowelsyndrome; colitis; detrusor instability; detrusor dysfunction; spasticbladder; neurogenic bladder; detrusor sphincter dyssynergia; detrusorhyperreflexia; detrusor areflexia; and combinations of one or more ofthese.

Apparatus 10 can be configured to treat a pelvic disorder selected fromthe group consisting of: pelvic pain; painful bladder syndrome; Hunner'sulcers or lesions; interstitial cystitis; pelvic floor dysfunction;endometriosis; vulvodynia; dyspareunia; pelvic adhesions; abdominaladhesions; irritable bowel syndrome; pelvic girdle pain; pudendal nerveentrapment; pudendal neuralgia; dysmenorrhea; Müllerian abnormalities;pelvic inflammatory disease; ovarian cysts; ovarian torsion; Loin painhematuria syndrome; proctitis; prostatitis; prostadynia; post-abdominalsurgical pain; post-pelvic surgical pain; hernia pain; post-herniasurgical pain; anal pain; rectal pain; perineal pain; groin pain; vulvarpain; vaginal pain; clitoral pain; colitis; and combinations of one ormore of these.

Apparatus 10 can be configured to treat one or more of the pelvicdisorders, bladder dysfunctions and/or and bowel dysfunctions listedabove, by stimulating (e.g., using bilateral and/or unilateralstimulation) one or more of the targets listed below.

In some embodiments, the stimulated targets include the sacral nerves(roots) S2, S3 and/or S4. One or more leads 265 (e.g., each includingone or more stimulation-delivering functional elements 260) can bepositioned to stimulate any or all of the three roots, on a single sideor both sides, in any bilateral or unilateral combination. The roots canbe accessed, with the patient lying in the prone position, bypositioning one or more leads 265 (e.g., percutaneously), with orwithout the use of fluoroscopy, ultrasound or any other imagingmodality, into one/any of the sacral foramen(a) from the posterioraspect of the sacrum. One or more leads 265 can be passed through theforamen to the anterior side of the sacrum, and/or one or more leads 265can remain inside the foramen(a).

In some embodiments, the sacral roots are approached rostrally, via thesacral canal in a retrograde manner. In these embodiments, one or moreleads 265 can be passed through the ligamentum flavum, just caudal to L5or via any of the intervertebral spaces from L5 to T12, into the spinalcanal. One or more leads 265 are then threaded, with or without the aidof visualization (fluoroscopy, ultrasound or other imaging modality), ina caudal (retrograde) manner to enter the sacral canal. One or moreleads 265 can be placed along the sacral canal, and each root can bestimulated individually and/or each root can be stimulated in concert,via one or more leads 265 positioned along the internal surface of thesacral canal, and spanning one or more foramina.

In some embodiments, one or more leads 265 are threaded from the spinalcanal into each and/or all sacral foramen(a), in an anterior direction.The sacral canal can also be accessed caudally by one or more leads 265,via the sacral hiatus in an anterograde manner.

In some embodiments, the sacral roots (S2, S3 and/or S4) are accessed asthey enter the spinal cord at the cauda equina. This access can beachieved by inserting the one or more leads 265 through the ligamentumflavum, at a location just caudal to L5, or via any of theintervertebral spaces from L5 to T12, into the spinal canal. The one ormore leads 265 can then be threaded, with or without the aid ofvisualization (fluoroscopy, ultrasound or other imaging modality), up tothe cauda equina, where the S2, S3 and/or S4 roots can be stimulatedwhere they enter the spinal cord, and/or the conus medullaris can bestimulated directly (e.g., in the same location).

In some embodiments, the pudendal nerve is stimulated through one ormore different approaches. The pudendal nerve contains both afferent andefferent fibers carried by S2, S3 and S4 roots. The pudendal fibers exitAlcock's canal near the ischial spine, where they spread out toinnervate to the bladder wall, perineum, anus, genitals and urethra.Pelvic and voiding disorders can be treated by stimulating pudendalnerve fibers. The fibers can be accessed at the Alcock's canal viavarious approaches. In one embodiment, a transperineal approach isachieved by positioning the patient in the lithotomy position andinserting the lead 265 midpoint between the ischial tuberosity and theanus. A lead 265 is inserted toward the ischial spine, which can bepalpated transvaginally or transrectally. The ischial spine can also bevisualized through a number of imaging modalities (e.g., fluoroscopy,x-ray, ultrasound, and the like). In another embodiment, a transvaginalapproach is achieved by positioning the patient in the lithotomyposition and inserting a lead 265 through the vaginal wall, adjacent tothe ischial spine (e.g., through the vaginal wall toward the ischialspine). In another embodiment, a posterior approach is achieved bylaying the patient in the prone position and inserting a lead 265 justmedial to the ischial tuberosity toward the ischial spine. Thisinsertion can be facilitated by rectal palpation of the ischial spineand through visualization via a number of imaging modalities (e.g.,fluoroscopy, x-ray, ultrasound, and the like).

In some embodiments, apparatus 10 is configured to stimulate pudendalafferents, such as by stimulating the dorsal genital nerve. These fibersare located just below the skin on the dorsum of the penis or justrostral to the clitoris. In some embodiments, pudendal afferents arestimulated periurethrally. One or more leads 265 can be insertedalongside the urethra to stimulate the pudendal fibers.

In some embodiments, apparatus 10 is configured to stimulate tibialnerve fibers, such as to treat one or more pelvic disorders (e.g.,voiding dysfunction). The tibial nerve can be accessed a few mm belowthe skin surface in the ankle immediately posterior to the medialmalleolus. Lead 265 can comprise a cylindrical SCS-type lead, which canbe inserted percutaneously in this location. Alternatively oradditionally, a direct (surgical) cut-down can be used to insert acylindrical lead or to apply a cuff electrode directly to the nerve. Thetibial nerve can also be accessed approximately half way up the lowerleg adjacent to the tibia. One or more leads 265 can be insertedpercutaneously in this location. Alternatively or additionally, a directcut-down can be used to insert lead 265 (e.g., a cylindrical lead or acuff electrode and/or hemi-cuff electrode applied directly to the nervein the mid-shin location). Tibial nerve fibers can be accessed in thepopliteal fossa behind the knee, for example percutaneously with a lead265 comprising a cylindrical lead, and/or via a direct cut-down, forexample with a lead 265 comprising either a cylindrical or cuffelectrode.

In some embodiments, apparatus 10 and one or more leads 265 areconstructed and arranged to stimulate the tibial and/or pudendal nervesvia a transvascular approach (i.e., stimulation energy delivered frominside a blood vessel to nerve tissue proximate the blood vessel), suchas via the femoral vein and/or artery, each of which provideintraluminal access to many other blood vessels (e.g., using standardinterventional techniques). The tibial nerve can be transvascularlystimulated by the popliteal vein and/or artery (e.g., by placing one ormore functional elements 260 in the popliteal vein and/or artery), at alocation behind the knee. The popliteal vein and/or artery can beintraluminally accessed from the femoral artery and vein. The tibialnerve also passes near the small saphenous vein, where it branches offof the popliteal vein. The posterior tibial vein and/or artery arepositioned adjacent to the tibial nerve, from the knee to the foot. Oneor more leads 265 can utilize one or more of these above locations tostimulate the tibial nerve.

In some embodiments, apparatus 10 and one or more leads 265 areconstructed and arranged to stimulate the pudendal nerve and/or sacralroots, such as using a lead 265 placed via the femoral vein and/orartery, which in turn provides intraluminal access to many vessels. Oneor more leads 265 can be configured to utilize any of the followingarteries and veins to stimulate the pudendal nerve and/or the sacralroots. One or more leads 265 can be constructed and arranged tostimulate a target site via a blood vessel selected from the groupconsisting of: the internal pudendal artery or vein (which branch off ofcommon iliac artery or vein, respectively); the inferior and superiorgluteal vein and/or artery; middle rectal, pudendal plexus and internaliliac vein and/or artery; medial and lateral sacral vein and/or artery;uterine and obturator vein and/or artery; and combinations of one ormore of these.

In some embodiments, apparatus 10 is configured to treat overactivebladder and/or urinary incontinence (singly or collectively “overactivebladder” herein). In some embodiments, apparatus 10 is configured totreat overactive bladder such as to reduce the effects of overactivebladder and/or to decrease use of one or more medications taken by thepatient to treat overactive bladder. In some embodiments, one or morefunctional elements 260 are positioned to stimulate tissue of thecentral nervous system or tissue and/or tissue of the peripheral nervoussystem to treat overactive bladder, such as to stimulate one or morenerves that control and/or are otherwise related to bladder function(e.g., to increase bladder capacity, improve bladder emptying, reduceurge incontinence and/or reduce stress incontinence). For example, oneor more functional elements 260 can be positioned to stimulate tibialnerve tissue and/or sacral nerve tissue (e.g., at least the S3 nerveroot) to treat overactive bladder. In some embodiments, lead 265 isconstructed and arranged to be positioned along one or more locations ofthe tibial nerve, such as a positioning performed using percutaneoustechnique (e.g., when lead 265 comprises a cylindrical SCS-type lead)and/or surgical (cut-down) techniques (e.g., when lead 265 comprise acuff electrode and/or hemi-cuff electrode applied directly to thenerve). The tibial nerve branches off of the sciatic nerve just abovethe knee, and runs along the length of the tibia, medial and lateral tothe tibia. The tibial nerve then passes posterior to the medialmalleolus prior to innervating the plantar surface of the foot. Lead 265can be constructed and arranged to access sites proximate the tibialnerve percutaneously and/or through an incision at the back of the kneein the popliteal fossa, along the tibia or behind the medial malleolus.The housing 210 can be placed anywhere in the leg when stimulating thetibial nerve. Lead 265 can be constructed and arranged to stimulate thetibial nerve through a transvascular approach, via the femoral veinand/or artery, each of which provide intraluminal access to manyvessels. The tibial nerve can be accessed by the popliteal artery andvein behind the knee, which are intraluminally accessible from thefemoral artery and vein, respectively. The tibial nerve also passes nearthe small saphenous vein, where it branches off of the popliteal vein.The posterior tibial vein and artery travel adjacent to the tibial nervefrom the knee to the foot. One or more leads 265 can be constructed andarranged to utilize any of these locations to transvascularly stimulatethe tibial nerve (e.g., transvascularly stimulate the tibial nerve viathe popliteal artery, popliteal vein, saphenous vein, posterior tibialartery and/or posterior tibial vein via a lead 265 advanced via thefemoral vein and/or artery). In these transvascular embodiments, thehousing 210 can be placed near the femoral or popliteal access point atlocations in the groin, perineum, scrotum, pelvis, hip, thigh, leg,behind the knee, buttocks, abdomen and/or low back. In the case ofsacral nerve stimulation, one or more leads 265 can be inserted throughan incision(s) made in the lower back, such that one or more functionalelements 260 are positioned proximate (e.g., in contact) with the sacralnerve root(s). The housing 210 can be placed anywhere in the groin,perineum, scrotum, pelvis, hip, thigh, leg, behind the knee, buttocks,abdomen and/or low back. Lead 265 (e.g., a lead 265 comprising a leadextension) can be extended underneath the skin (e.g., tunneled) to asecond incision (e.g., across the flank to the lower abdomen, across themidline to the buttocks, or low back), and a third incision can be made(e.g., in the abdomen, back or buttocks) where housing 210 can beinserted and connected to lead 265. Alternatively, housing 210 can beinserted at another internal location. If lead 265 is already connected(e.g., attached in manufacturing) to housing 210, lead 265 can beadvanced in the opposite direction, such as from the third incision, tothe second incision, to the first incision (if three incisions aremade), or housing 210 can be advanced under the tissue from incision 1to incision 2 or from incision 2 to incision 3. In some embodiments,only 1 or 2 incisions are performed. In some embodiments, such as whenlead 265 is already connected (e.g., attached in manufacturing) tohousing 210, lead 265 and housing 265 are implanted. In someembodiments, a first lead 265 and a first housing 210 (pre-attached orattachable) are utilized in a dose titration or other “trialingprocedure”, and a second lead 265 and housing 210 (pre-attached orattachable) are implanted in the patient for subsequent treatment of thepatient.

In some embodiments, one or more functional elements 260 are positionedto perform posterior tibial nerve stimulation (PTNS), also referred toas percutaneous tibial nerve stimulation, such as to perform an indirectform of neuromodulation to treat bladder voiding dysfunction. Theposterior tibial nerve is derived from the lumbar-sacral nerves (L4-S3),which innervate the bladder detrusor and pelvic floor. In someembodiments, one or more functional elements 260 can be positioned toperform retrograde stimulation of the sacral nerve plexus and restorethe balance between bladder inhibitory and excitatory control systems ofthe bladder. One or more functional elements 260 can be positioned abovethe ankle, proximate and/or into the tibial nerve. Implantable device200 can deliver stimulation energy to the functional elements 260comprising low-voltage electrical stimulation configured to producesensor and/or motor responses. Apparatus 10 can be configured to providecontinuous and/or intermittent stimulation to tissue, such as tomodulate transmission of excitatory nerve signals to the bladdermuscles. In some embodiments, system 20 is configured to deliver aseries of repeated stimulation periods, such as a regimen ofapproximately: weekly thirty minute sessions of stimulation for twelveweeks. In some embodiments, system 20 is configured to provide daily orhourly sessions that deliver stimulation for between 10 minutes and 60minutes. In some embodiments, apparatus 10 is configured to achieve anapproximate 50% reduction in urinary urge incontinence and/or urinaryurgency/frequency episodes.

In some embodiments, apparatus 10 is configured to provide temporarystimulation of tissue to treat overactive bladder, such as by usingtrialing device 80 described hereabove in reference to FIG. 1, such asto provide power and/or date to one or more implantable devices 200 toconfirm acceptable improvement of the patient's overactive bladder(e.g., successful stimulation of one or more sacral nerves, tibialnerves or other tissue), before closing an incision or otherwise fullyimplanting one or more implantable devices 200. In some embodiments, atemporary stimulation is provided for up to one week or up to one month.In some embodiments, one or more implantable devices 200 are left inplace if the temporary stimulation period is successful or unsuccessful(e.g., left implanted due to its small size or otherwise minimal impacton the patient).

In some embodiments, apparatus 10 is configured to stimulate a region ofthe pelvic floor, such as to: change the reflex thresholds of thebladder muscles responsible for bladder emptying, strengthen and/orotherwise improve the condition of the muscles that maintain closure onthe bladder outlet; change the state of the neural pathways, musculatureand/or bladder during and beyond the period stimulation; and/orotherwise decrease the severity of urinary incontinence. In someembodiments, one or more functional elements 260 are positioned tostimulate periurethral muscles. In some embodiments, one or morefunctional elements 260 are positioned to stimulate tissue of the vaginaor anus. In some embodiments, one or more functional elements 260 arepositioned to stimulate sphincter muscles for controlling the bladder,such as two functional elements 260 positioned on either side of theurethral orifice. In these embodiments, housing 210 can be implanted insuprapubic region or in the perineum. In some embodiments, lead 265comprises (e.g., on a distal portion) a pessary ring comprising twofunctional elements 260. In some embodiments, functional elements 260comprise periurethral electrodes configured to stimulate pudendalafferents.

As described above, apparatus 10 can be configured for treating numerousdiseases, disorders or other undesirable patient conditions, such asfecal incontinence. Injury of nerves that sense stool in the rectum canlead to fecal incontinence. In some embodiments, one or more functionalelements 260 (e.g., one or more electrical, magnetic, light or otherenergy delivery elements) of one or more leads 265 and/or one or moreimplantable devices 200 are configured to stimulate tissue to treatfecal incontinence, such as to treat tissue selected from the groupconsisting of: sacral nerve tissue; tissue whose stimulation strengthensmuscles of the bowel and/or rectum; and combinations of one or more ofthese. In these fecal incontinence applications, leads 265 can beimplanted in a location selected from the group consisting of: thepelvic girdle; the sacral foramina; the lower back; the upper buttock;and combinations of one or more of these, such as to stimulate sacralnerve tissue. Leads 265 can be anchored via lead anchors (silicone orother materials), suture, staples, clips, adhesive and the like, such asan attachment to the underlying fascia of target tissue to bestimulated. In some embodiments, apparatus 10 is configured to treatboth fecal incontinence and a bladder disorder such as overactivebladder, such as when one or more functional elements 260 are configuredto deliver energy to sacral nerve or other tissue.

In some embodiments, apparatus 10 is configured to treat fecalincontinence, overactive bladder (i.e., overactive bladder and/orurinary incontinence), and/or pelvic disorders, and implantable device200: comprises between 1 and 16 functional elements 260, such as four ormore electrodes; delivers electrical stimulation energy at a range ofapproximately between 10 Hz and 15 Hz (or a range of between 5 Hz and 25Hz); delivers electrical stimulation energy with a pulse width ofapproximately between 180 μsec and 240 μsec (or between 1 μsec and 200μsec); provides electrical stimulation energy with an amplitude ofapproximately 0.1V to 8.5V (e.g., providing a current between 0.1 mA to10 mA, which can be adjusted in increments between 0.01 mA and 0.1 mA),such as an amplitude between 0.4V and 2.0V; delivers continuouselectrical stimulation energy; delivers intermittent electricalstimulation energy, such as with a period between 8 seconds and 24seconds and/or an on time between 8 seconds and 16 seconds; or an ontime of several hours followed by an off time of several hours (such as8 hours of stimulation ON and 16 hours of stimulation OFF or 16 hours onand 8 hours off, and 12 hour on and 12 hours off; delivers monopolarelectrical energy; delivers bipolar electrical energy; and combinationsof one or more of these.

In some embodiments, apparatus 10 is configured to treat an occipitalneuralgia, such as migraine headache, headache and/or cluster headache,and one or more functional elements 260 (e.g., small column paddleelectrodes, standard paddle electrodes or other electrodes) arepositioned to stimulate nerve tissue selected from the group consistingof: occipital; supraorbital; infraorbital; greater occipital nerve(GON); lesser occipital nerve (LON); both supraorbital and GON;supratrochlear; sphenopalatine (SPG); and combinations of one or more ofthese.

In some embodiments, apparatus 10 is configured to treat neuralgia, suchas a neuralgia resulting from surgery (e.g., groin, shoulder, lungand/or amputation), trauma and/or phantom pain, and one or morefunctional elements 260 are positioned to stimulate nerve tissue.

In some embodiments, apparatus 10 is configured to treat neuralgia, suchas a neuralgia resulting from groin surgery (e.g., hernia or other groinsurgery), and one or more functional elements 260 are positioned tostimulate nerve tissue selected from the group consisting of:ilioinguinal; genitofemoral; iliohypogastric; and combinations of one ormore of these.

In some embodiments, apparatus 10 is configured to treat neuralgia, suchas a neuralgia resulting from shoulder surgery, and one or morefunctional elements 260 are positioned to stimulate axial nerve tissue(e.g., one or more functional elements 260 positioned on a lead 265implanted in a suprascapular location).

In some embodiments, apparatus 10 is configured to treat neuralgia, suchas a neuralgia resulting from lung surgery, and one or more functionalelements 260 are positioned to stimulate intercostal nerve tissue.

In some embodiments, apparatus 10 is configured to treat neuralgia, suchas a neuralgia associated with carpal tunnel syndrome, and one or morefunctional elements 260 are positioned to stimulate median nerve tissue.

In some embodiments, apparatus 10 is configured to treat neuralgia, suchas a neuralgia associated with temporomandibular joint disorder (TMJ),and one or more functional elements 260 are positioned to stimulate V2of trigeminal nerve tissue.

In some embodiments, apparatus 10 is configured to treat neuralgia, suchas a facial neuralgia, and one or more functional elements 260 arepositioned to stimulate trigeminal nerve tissue.

In some embodiments, apparatus 10 is configured to treat neuralgia, suchas a leg (sciatic) neuralgia, and one or more functional elements 260are positioned to stimulate nerve tissue proximal a contributing lesion.

In some embodiments, apparatus 10 is configured to treat pelvic pain,such as interstitial cystitis and/or bladder pain, and one or morefunctional elements 260 are positioned to stimulate peripheral nervoussystem tissue (e.g., pudendal tissue and/or S-2, S-3 and/or S-4 roots)and/or central nervous system tissue (e.g., lower spinal cord and/or S3neural foramen).

In some embodiments, apparatus 10 is configured to treat pelvic pain,such as anal pain, and one or more functional elements 260 arepositioned to stimulate peripheral nerve tissue such as pudendal tissueand/or S-2, S-3 and/or S-4 roots.

In some embodiments, apparatus 10 is configured to treat subcutaneouspain, and one or more functional elements 260 (e.g., paddle electrodes)are positioned to stimulate nerve tissue.

In some embodiments, apparatus 10 is configured to treat diabeticneuropathy, such as painful diabetic neuropathy, and one or morefunctional elements 260 are positioned proximate the lower spinal cord(e.g., to stimulate S3 nerves) or other body location to stimulate nervetissue.

In some embodiments, apparatus 10 is configured to treat visceral pain,angina and/or other pain, and one or more functional elements 260 arepositioned to stimulate the vagus nerve.

In some embodiments, apparatus 10 is configured to treat peripheralvascular disease, diabetic neuropathy and/or other conditions associatedwith diabetes, such as to treat a disease or disorder selected from thegroup consisting of: peripheral diabetic neuropathic pain; painfuldiabetic peripheral neuropathy; peripheral vascular disease; peripheralarterial disease; peripheral artery disease; cardiac autonomicneuropathy; diabetic autonomic neuropathy; diabetic sensory neuropathy;diabetic motor neuropathy; diabetic sensorimotor neuropathy; diabeticmuscular atrophy; diabetic neurovascular disease; and combinations ofone or more of these. In these embodiments, lead 265 can be positionedproximate a nerve in the foot, leg, arm and/or sacrum (e.g., such thatone or more functional elements 260 are positioned proximate the nerveto be stimulated). In some embodiments, lead 265 is positioned tostimulate the dorsal root ganglia to treat diabetic neuropathy (e.g.,diabetic neuropathy of the hand and/or foot). Lead 265 can be implantedpercutaneously and/or surgically as described herein. Lead 265 and/orone or more functional elements 260 can comprise a paddle electrode,such as one or more paddle electrodes implanted in the foot, leg and/orarm. Lead 265 and/or one or more functional elements 260 can comprise acuff or hemi-cuff electrode surgically implanted around a nerve in thefoot, leg and/or arm. Apparatus 10 can be configured to provide spinalcord stimulation, either through percutaneous insertion of one or moreleads 265 in the epidural space or surgical implantation of a lead 265comprising a paddle lead positioned in the epidural space. Apparatus 10can be configured to provide transvascular stimulation of nerves in thefoot, leg and/or arm, (e.g., to treat diabetic neuropathy) such as whenone or more leads 265 are interventionally advanced into the venous orarterial system. Leads 265 can be positioned using percutaneoustransforaminal placement in the sacral foramina, such as for treatmentof foot or leg disorders. Leads 265 can be constructed and arranged forcephalocaudal insertion (retrograde) into the epidural space or sacralcanal, such as for treatment of foot or leg disorders. Leads 265 can beconstructed and arranged to provide dorsal root ganglion stimulation,such as for treatment of trunk, neck, head, back, foot, leg, arm and/orhand disorders.

One or more leads 265 (e.g., each including one or more functionalelements 260) can be constructed and arranged to stimulate tibial nervefibers, such as to treat diabetic neuropathy and/or diabetic relatedmaladies of the foot. The tibial nerve can be accessed as describedherein.

One or more leads 265 can be configured to stimulate the peroneal nerveor saphenous nerve, such as at one or more locations describedherebelow. The peroneal nerve can be accessed percutaneously orsurgically behind the knee in the popliteal fossa where it branches offof the sciatic nerve. It can also be accessed as it wraps around thelateral aspect of the knee just prior to diving under the fibularislongus and extensor digitorum longus muscles. The deep fibular nerve (abranch of the peroneal nerve) innervates top medial foot, whereas thesuperficial fibular (peroneal) innervates top of both medial and lateralfoot. In some embodiments, functional element 260 comprises one or moreelectrodes positioned in the anterior tibial vein and/or artery totransvascularly stimulate the deep fibular nerve. The saphenous nervecomes off the femoral nerve deep in the thigh. It passes around themedial aspect of the knee medial to the patella. It then runs down themedial shin adjacent to the tibia, gastrocnemius and soleus muscleswhere it can be accessed surgically or percutaneously. It then surfacesjust as it warps around the anterior aspect of the medial malleoluswhere it supplies the medial posterior foot in front of heel. The medialsural cutaneous nerve comes off of the tibial at the popliteal fossa,then runs down the back of the calf (over the gastrocnemius) and wrapsaround the posterior aspect of the lateral malleolus before innervatingthe lateral aspect of the sole and heel. In some embodiments, thesaphenous nerve is transvascularly stimulated by positioning one or morefunctional elements 260 in a blood vessel selected from the groupconsisting of: femoral vein; femoral artery; great saphenous vein; greatsaphenous artery; and combinations of one or more of these. In someembodiments, the sural nerve is stimulated. In these embodiments, thesural nerve can be transvascularly stimulated by positioning one or morefunctional elements 260 in the saphenous vein.

One or more leads 265 can be configured to stimulate the median nerve,ulnar nerve and/or radial nerve. The median nerve can be accessedpercutaneously in the upper arm lateral to the brachial vein and/orartery, but medial to the biceps muscle, whereas the ulnar nerve runsmedial to the brachial artery in the upper arm. The median nerve passesthrough the anterior aspect of the elbow under the bicipitalaponeurosis. The ulnar nerve runs medial and posterior to the medialepicondyle of the humerus. The median nerve can also be accessed in thewrist just proximal to the palm and the palmar carpal ligament. Theulnar nerve can be accessed just proximal to the palmar carpal ligamentadjacent to the pisiform. The radial nerve can be accessedpercutaneously just as it passes anterior to the lateral epicondyle. Insome embodiments, apparatus 10 can be configured to transvascularlystimulate at least one of a median nerve, an ulnar nerve or a radialnerve, and functional element 260 can comprise one or more electrodespositioned in a vessel selected from the group consisting of: brachialvein; brachial artery; basilic vein; basilic artery; deep vein of thearm; deep artery of the arm; and combinations of one or more of these.In some embodiments, apparatus 10 can be configured to transvascularlystimulate at least one of a median nerve or an ulnar nerve, andfunctional element 260 can comprise one or more electrodes positioned ina vessel selected from the group consisting of: brachial vein; brachialartery; and combinations of one or more of these. In some embodiments,apparatus 10 can be configured to transvascularly stimulate the radialnerve, and functional element 260 can comprise one or more electrodespositioned in a vessel selected from the group consisting of: deep veinof arm; deep artery of arm; basilic vein; radial collateral vein; radialcollateral artery; medial collateral vein; medial collateral artery;radial vein; radial artery; and combinations of one or more of these. Insome embodiments, apparatus 10 can be configured to transvascularlystimulate the medial cutaneous nerve, and functional element 260 cancomprise one or more electrodes positioned in the basilic vein. In someembodiments, apparatus 10 is configured to transvascularly stimulate theulnar nerve, and functional element 260 can comprise one or moreelectrodes positioned in a vessel selected from the group consisting of:ulnar collateral vein; ulnar collateral artery; ulnar vein; ulnarartery; and combinations of one or more of these. In some embodiments,apparatus 10 is configured to transvascularly stimulate the mediannerve, and functional element 260 can comprise one or more electrodespositioned in a vessel selected from the group consisting of: brachialvein; brachial artery; ulnar vein; ulnar artery; and combinations of oneor more of these.

As described herein, one or more leads 265 can be positioned tostimulate the spinal cord, such as via percutaneous insertion of a lead265 in the epidural space or surgical implantation of the lead 265(e.g., a paddle lead) in the epidural space. A lead 265 can be placedsuch that one or more functional elements 260 (e.g., one or moreelectrodes) are positioned from T5-S5, such as to capture the area ofpain or reduced circulation of the leg or foot. One or more functionalelements 260 of one or more leads 265 can be positioned from C2 to T8,such as to capture the area of pain or reduced circulation of the arm orhand. One or more leads 265 can be placed along the midline,unilaterally and/or bilaterally over the dorsal columns, in the gutter(over dorsal roots) and/or in the dorsal root entry zone. Leads 265 canspan several vertebral levels or they can be positioned to span a singlelevel.

One or more functional elements 260 (e.g., one or more electrodesattached to one or more leads 265) can be positioned to transvascularlystimulate one or more nerves, such as one or more nerves in the foot,leg and/or arm, such as when the one or more functional elements 260 areimplanted within one or more blood vessels of the venous and/or arterialsystem.

In the leg, the tibial nerve, sacral roots and/or deep fibular nerve canbe stimulated, such as when a lead 265 accesses the tissue to bestimulated through a transvascular approach, such as via the femoralvein and/or artery, as described herein. The deep fibular nerve can bestimulated by one or more functional elements 260 positioned in theanterior tibial vein and/or the anterior tibial artery. In the arm, themedian nerve, ulnar nerve, superior ulnar nerve, medial cutaneous nerveand/or radial nerve can be stimulated, such as when lead 265 accessesthe tissue to be stimulated through a transvascular approach, such asvia the brachial vein and/or artery, the basilic vein and/or artery,and/or the deep vein and/or artery.

One or more functional elements 260 (e.g., one or more electrodesattached to one or more leads 265) can be positioned to stimulate dorsalroot ganglia that supply the following nerves (e.g., to treat the legand/or foot): common peroneal (L4-S2); tibial (L4-S3); femoral (L2-L4);and combinations of one or more of these. One or more functionalelements 260 (e.g., one or more electrodes attached to one or more leads265) can be positioned to stimulate dorsal root ganglia that supply thefollowing nerves (e.g., to treat the hand and/or arm): radial (C5-T1);median (C5-T1); ulnar (C7-T1); and combinations of one or more of these.In these embodiments, one or more leads 265 can be passed through theintervertebral foramina, either unilaterally or bilaterally, at a singlevertebral level or at multiple vertebral levels.

In some embodiments, apparatus 10 is configured to treat post-amputationpain, such as to treat a disease or disorder selected from the groupconsisting of: phantom limb pain; phantom stump pain; acute andpersistent stump pain; limb pain; neuroma; Morton's neuroma;neurilemoma; neurolemoma; Schwann cell tumor; phantom limb itch; phantomlimb sensations; and combinations of one or more of these. Apparatus 10can be configured to treat the conditions associated withpost-amputation pain (i.e., stump pain), such as by using a highfrequency alternating current (HFAC) block approaches. In theseembodiments, one or more leads 265 can be implanted such that one ormore functional elements 260 stimulate one or more nerves in the leg,arm and/or sacrum. One or more leads 265 can be surgically implanted,such as when lead 265 comprises a paddle electrode positioned near anerve in the foot, leg or arm and/or a cuff electrode or hemi-cuffelectrode positioned to at least partially surround a nerve in the foot,leg or arm. One or more leads 265 can be positioned to stimulate thespinal cord, such as via a percutaneous insertion of the leads 265 inthe epidural space or surgical implantation of the lead 265 (e.g., apaddle lead) in the epidural space. One or more leads 265 can bepositioned to provide transvascular stimulation of nerves in the leg orarm, such as when one or more functional elements 260 are implantedwithin a vein or artery. One or more leads 265 can be implanted usingpercutaneous transforaminal placement in the sacral foramina, such asfor treatment of leg stump pain. One or more leads 265 can be implantedusing cephalocaudal insertion (retrograde) into the epidural space orsacral canal, such as for treatment of leg stump pain. One or more leads265 can be positioned to perform dorsal root ganglion stimulation and/orblock, such as for treatment of leg and/or arm stump pain.

In some embodiments, apparatus 10 is configured to treat occipitaland/or headache (HA) pain, such as when apparatus 10 is configured totreat a disease or disorder selected from the group consisting of:occipital neuralgia; cervicogenic headache; tension headache; chronicand episodic migraine headache; tension headache; hemicrania continua;trigeminal autonomic cephalalgias (TACs); chronic and episodic clusterheadache; chronic and episodic paroxysmal hemicranias; short-lastingunilateral neuralgiform headache attacks with conjunctival injection andtearing (SUNCT); short-lasting unilateral neuralgiform headache attackswith cranial autonomic symptoms (SUVA); long-lasting autonomic symptomswith hemicrania (LASH); post-traumatic headache; and combinations of oneor more of these.

Apparatus 10 can be configured to treat the conditions associated withheadache pain and/or occipital neuralgia by stimulating one or morenerves in the head, such as one or more nerves selected from the groupconsisting of: greater and/or lesser occipital nerve (e.g., which arisefrom C2 and C3); the greater and/or lesser auricular nerves (e.g., whichalso arise from C2/C3); the third (least) occipital nerve (e.g., whicharises from C3); and combinations of one or more of these. Theinfraorbital or supraorbital nerves can be access subcutaneously belowand above the eye, respectively. Apparatus 10 can be configured tostimulate auriculotemporal, supratrochlear and/or sub-occipital nerves.To stimulate any of these nerves, lead 265 (e.g., a cylindrical SCS-typelead) can be inserted percutaneously either subcutaneously or under themuscle. Alternatively, surgical (e.g., direct cut-down) can be performedto insert lead 265 (e.g., a cylindrical lead, a paddle lead, a cuff orhemi-cuff electrode) proximate, one and/or around these nerves.Alternatively or additionally, the nerves can be accessedtransvascularly as described herein (e.g., when one or more functionalelements 260 are implanted in a blood vessel). Housing 210 can beimplanted anywhere in the head under the skin, including: behind theear, back of the head, the neck, in the face, and the like, where an oneor more external devices 500 can be positioned in, on and/or within ahat, headband, glasses, goggles, earpiece, necklace, patch, and thelike. Apparatus 10 can be configured to treat headache pain and/oroccipital neuralgia by stimulating tissue in the cervical spinal cord(C2-C3), for example proximate the location the nerve enters the cordfrom the foramen. One or more leads 265 can be placed over the dorsalcolumns, in the gutter, over the dorsal root entry zone and/or out inthe foramen at the dorsal root ganglion. In some embodiments, thetrigeminal and pterygopalatine ganglia are accessed by inserting one ormore leads 265 through the face or the roof of the mouth. In theseembodiments, housing 210 can be placed anywhere in the head under theskin, as described herein.

In some embodiments, apparatus 10 is configured to treat post-herpeticneuralgia, such as to treat a disease or disorder selected from thegroup consisting of: shingles; herpes zoster; zoster; zona; varicellazoster virus infection; zoster sine herpete; fever blisters; herpeszoster blisters; herpes zoster rash; and combinations of one or more ofthese. In some embodiments, apparatus 10 is configured to treatpost-herpetic neuralgia using high frequency alternating current (HFAC)block approaches. In these embodiments, one or more leads 265 can beimplanted such that one or more functional elements 260 stimulate one ormore nerves in the leg, arm, torso and/or sacrum. One or more leads 265can be surgically implanted, such as when lead 265 comprises a paddleelectrode positioned near a nerve in the foot, leg, torso and/or armand/or a cuff electrode or hemi-cuff electrode positioned to at leastpartially surround a nerve in the foot, leg, torso or arm. One or moreleads 265 can be positioned to stimulate the spinal cord, such as via apercutaneous insertion of the leads 265 in the epidural space orsurgical implantation of the lead 265 (e.g., a paddle lead) in theepidural space. One or more leads 265 can be positioned to providetransvascular stimulation of nerves in the leg, torso and/or arm, suchas when one or more functional elements 260 are implanted within a veinor artery. One or more leads 265 can be implanted using percutaneoustransforaminal placement in the sacral foramina, such as for treatmentof leg or foot pain. One or more leads 265 can be implanted usingcephalocaudal insertion (retrograde) into the epidural space or sacralcanal, such as for treatment of leg or foot pain. One or more leads 265can be positioned to perform dorsal root ganglion stimulation and/orblock, such as for treatment of leg, torso and/or arm pain.

In some embodiments, apparatus 10 is configured to treat angina, such asto treat a disease or disorder selected from the group consisting of:angina; chest pain caused by reduced blood flow to the heart muscle;chest pain associated with coronary artery disease such as squeezing,pressure, heaviness, tightness or pain in the chest; recurring anginapectoris; acute angina pectoris; chronic angina pectoris; acute coronarysyndrome; chest pain; coronary artery spasms; microvascular angina;Prinzmetal's angina; angina inversa; stable or common angina; unstableangina; variant angina; and combinations of one or more of these.

In some embodiments, apparatus 10 is configured to treat carpal tunnelsyndrome, such as to treat a disease or disorder selected from the groupconsisting of: median nerve entrapment; tingling and/or numbness infingers or hand; median nerve irritation or compression; narrowing ofthe carpal tunnel; and combinations of one or more of these.

In some embodiments, apparatus 10 is configured to treat erectiledysfunction (ED), such as to treat a disease or disorder selected fromthe group consisting of: impotence; male sexual dysfunction; inabilityto develop or maintain an erect penis; cardiogenic ED; vasculogenic ED;diabetic ED; neurogenic ED; traumatic ED; post-prostatectomy ED;hormonal ED; hyopogonadism; pharmacological ED; and combinations of oneor more of these.

In some embodiments, apparatus 10 is configured to treat complexregional pain syndrome (CRPS), such as to treat a disease or disorderselected from the group consisting of: CRPS type 1; CRPS type 2; reflexsympathetic dystrophy; causalgia; reflex neurovascular dystrophy;amplified musculoskeletal pain syndrome; systemic autonomicdysregulation; neurogenic edema; musculoskeletal pain; and combinationsof one or more of these.

In some embodiments, implantable device 200 has an internal battery orother power supply such that stimulation (e.g., stimulation energyand/or a stimulation agent) can be delivered to one or more locationswithin a patient for an extended time period (e.g., at least 1 hour, atleast 1 day, at least 1 month or at least 1 year), without receiving apower transmission (e.g., as described herein from an external devicesuch as external device 500) during that time period. In someembodiments, at least a portion of a single pulse of energy (e.g., atleast a single phase) is delivered by implantable device 200 usingenergy provided by an internal power supply such as a battery or acapacitor. In these embodiments, data can be transmitted by one or moreof an external device 500 and/or programmer 550, such as to activate ormodify stimulation being delivered, with or without also transmittingpower.

In some embodiments, implantable device 200 comprises one or morecomponents configured to receive transmitted power (e.g., via anexternal device 500), receive transmitted data (e.g., via an externaldevice 500 and/or programmer 550) and/or deliver stimulation (e.g.,deliver stimulation energy and/or a stimulation agent).

In some embodiments, one or more implantable devices 200 are configuredto deliver stimulation energy (e.g., via one or more functional elements260 comprising an electrode) with a stimulation waveform comprising oneor more high frequency signals (e.g., a signal comprising one or morehigh frequency components). For example, one or more implantable devices200 can deliver one or more stimulation waveforms comprising one or moresignals above 600 Hz, such as one or more signals above 1.0 kHz, 1.2kHz, 5 kHz, 10 kHz or 25 kHz.

In these embodiments, the delivered stimulation waveform can beconfigured to be void of (i.e., not include) one or more lower frequencysignals, such as by not including any signals at a frequency below 100Hz, below 500 Hz, below 1000 Hz, below 1200 Hz or below 1500 Hz.

One or more implantable devices 200 can be configured to deliverstimulation energy with a stimulation waveform that varies over time. Insome embodiments, one or more stimulation parameters of the stimulationwaveform are randomly varied over time, such as by using a probabilitydistribution as described herein. Each stimulation waveform can compriseone or more pulses, such as a group of pulses that are repeated atregular and/or irregular intervals. In some embodiments, a pulse cancomprise delivery of electrical energy, such as electrical energydelivered in one or more phases (e.g., a pulse comprising at least acathodic portion and an anodic portion). In some embodiments, single orgroups of pulses are provided at time-varying modes of repetition (e.g.,regular intervals for a period, then a period of irregular intervals) orat regular intervals with occasional (random) spurious pulses inserted(creating a single irregular event in an otherwise regular series).Non-limiting examples of waveform variations include: a variation infrequency (e.g., frequency of one or more signals of the waveform);variation of a signal amplitude; variation of interval time period(e.g., at time period between pulses or a time period between pulsetrains); variation of a pulse width; multiple piecewise or continuousvariations of one of more stimulation parameters in a single pulse(e.g., multi-step, multi-amplitude in one “super-pulse”); variation ofpulse symmetry (e.g., via active drive, passive recovery and/oractive-assisted passive recovery); variation of stimulation energy overa time window and/or overlapping time windows; variation of the power inthe frequency spectrum of the stimulation waveform; and combinations ofone or more of these. In some embodiments, apparatus 10 and/orimplantable device 200 can be configured to vary a stimulation waveform“systematically” such as a variation performed temporally (e.g., onpredetermined similar or dissimilar time intervals) and/or a variationperformed based on a parameter, such as a measured parameter that can bebased on a signal produced by a sensor of implantable device 200 oranother component of apparatus 10. Alternatively or additionally,apparatus 10 and/or implantable device can be configured to vary astimulation waveform randomly, such as is described herein. Randomvariation shall include discrete or continuous variations that can beselected from a distribution, such as a probability distributionselected from the group consisting of: a uniform distribution; anarbitrary distribution; a gamma distribution; a normal distribution; alog-normal distribution; a Pareto distribution; a Gaussian distribution;a Poisson distribution; a Rayleigh distribution; a triangulardistribution; a statistic distribution; and combinations of one or moreof these. Random pulses or groups of pulses can be generated based onrandomly varying one or more stimulation signal parameters as describedherein. One or more stimulation parameters can be varied randomlythrough the use of one or more probability distributions, as describedherebelow.

In some embodiments, the amplitude of a signal delivered by one or moreimplantable devices 200 is adjusted to prevent discomfort to the patient(e.g., paresthesia or other undesired condition) from the stimulationsignal. In some embodiments, the amplitude of the stimulation signal canbe ramped (e.g., up and/or down), a single time or multiple times (e.g.,continuously or intermittently). In some embodiments, a titrationprocedure can be performed to “set” one or more stimulation parametersbased on avoiding patient discomfort.

In some embodiments, one or more implantable devices 200 (e.g., asdescribed hereabove in reference to FIG. 1) are configured to deliverstimulation energy (e.g., via one or more functional elements 260comprising an electrode) with a stimulation waveform comprising one ormore waveform patterns. The stimulation waveforms delivered can beconfigured to treat various conditions of a patient. Each stimulationwaveform can comprise a series of continuous pulses, intermittentpulses, and/or spurious pulses (e.g., occasional events in an otherwisecontinuous stream). Each pulse can comprise a pulse train that isrepeatedly delivered by implantable device 200, the train comprising oneor more cathodic pulses and/or one or more anodic pulses. In someembodiments, implantable device 200 delivers a multiphasic pulsecomprising at least two cathodic pulses and/or anodic pulses, with orwithout any time between each pulse. For example, implantable device 200can deliver a biphasic pulse comprising a cathodic pulse followed by ananodic pulse, a triphasic pulse comprising a cathodic pulse followed byan anodic pulse followed by a second cathodic pulse, or any series oftwo or more cathodic and/or anodic pulses. In some embodiments,delivered pulses are exponential in nature (e.g., comprise anexponential portion), such as dynamic return pulses that exceed aminimum current (e.g., at least 1 mA, 10 mA or 50 mA) for a shortduration (e.g., for approximately 1 μsec), and then decay to lowercurrent levels (e.g., a level of approximately 100 nA), with a timeconstant on the order of 1 μsec to 100 μsec.

The stimulation waveforms delivered by implantable device 200 cancomprise one or more high frequencies (e.g., as described herein). Thestimulation waveform frequency or other stimulation parameter can be setand/or adjusted (hereinafter “adjusted”) to optimize therapeutic benefitto the patient and minimize undesired effects (e.g., paresthesia orother patient discomfort). In some embodiments, a stimulation waveformis adjusted based on a signal produced by a sensor of apparatus 10(e.g., a sensor of implantable device 200, such as a functional element260 configured as a sensor or other sensor of implantable device 200 asdescribed hereabove). Adjustment of a stimulation waveform parameter canbe performed automatically by the implantable device 200 and/or via anexternal device 500 and/or programmer 550).

In some embodiments, a pulse shape can be varied, such as a pulse shapecomprising: a sinusoidal geometry; a square geometry (e.g., a waveformcomprising a square wave); a rectangular geometry; a triangulargeometry; (e.g., symmetric or asymmetric); a trapezoidal geometry; asawtooth geometry; a ramped geometry; an exponential geometry; apiece-wise step function geometry; a root-raised cosine geometry; andcombinations of one or more of these.

In some embodiments, a charge recovery phase (e.g., anodal phase) isvaried by implantable device 200.

Inter-pulse gap, the time between one or more pulses (e.g., a biphasicor other multiphasic pulse that is repeated continuously), can be variedsystematically and/or randomly by implantable device 200. In someembodiments, inter-pulse gap between one or more pulses comprises zerotime (i.e., a first pulse is immediately followed by a similar ordissimilar second pulse). In some embodiments, inter-pulse gap is variedsystematically, such as on a routine basis (i.e., temporally) and/orvaried based on a signal produced by a sensor of apparatus 10.Alternatively or additionally, inter-pulse gap can be varied randomly.such as a random variation based on a distribution (e.g., a probabilitydistribution with a pre-determined shape) as described herebelow.

In some embodiments, implantable device 200 delivers a stimulationwaveform comprising a series of frequency modulated (FM) pulses, suchthat the frequency of stimulation varies. Implantable device 200 can beconfigured to deliver a frequency modulated stimulation waveformcomprising a carrier signal, at a carrier frequency, that is modulatedcontinuously between a first frequency and a second frequency. Forexample, implantable device 200 can deliver a stimulation waveform thatmodulates between 2.0 kHz and 3.0 kHz every second (e.g., comprising acarrier signal at 2.5 kHz that is modulated at 1 Hz) with a modulationrange (the excursion from the carrier signal) of +/−500 Hz. In someembodiments, implantable device 200 can deliver a stimulation waveformthat comprises: a carrier frequency between 1 kHz and 50 kHz, amodulation frequency between 0.1 Hz and 10 kHz and/or a modulation rangebetween 1 Hz and the carrier frequency.

In some embodiments, implantable device 200 delivers a stimulationwaveform comprising a series of amplitude modulated (AM) pulses, suchthat the amplitude of stimulation varies (e.g., varying the amplitude ofthe voltage and/or current of the stimulation signal). The amplitude ofdelivered current can be varied in a single amplitude modulated sweep,such as a sweep from 2 mA to 3 mA. In some embodiments, amplitude of asignal can be varied continuously, such as when current is variedbetween 2 mA and 3 mA every second (e.g., a signal comprising amodulation frequency of 1 Hz). In these embodiments, the depth ofmodulation would be 33%, where depth of modulation is equal to 1-[lowerrange/upper range]. In some embodiments, amplitude of delivered currentfluctuates between 1 mA and 3 mA (i.e., a depth of modulation of 66%),while in other embodiments, current fluctuates between 0 mA and 3 mA(e.g., a depth of modulation of 100%). In some embodiments, implantabledevice 200 is configured to deliver an amplitude modulated signalcomprising: a carrier frequency between 1 Khz and 50 kHz; a modulationfrequency between 0.1 Hz and the carrier frequency and/or a depth ofmodulation between 0.1% and 100%.

In some embodiments, implantable device 200 delivers a stimulationwaveform comprising delivery of continuously balanced analog currentwaveforms, for example from a differential Howland current source. Inthese embodiments, there are not independent pulses, but rather there istrue analog frequency and amplitude modulation. Periods of deliveringstimulation (or presence of balanced differential analog stimulation)and periods of no stimulation (e.g., a quiescent period) can beincluded. In some embodiments, controller 250 comprises one or morereconfigurable stimulation blocks including one or more Howland or othercurrent sources. The one or more current sources (e.g., two or morecurrent sources) can each be attached to a functional element 260 (e.g.,in a monopolar configuration when the current source is also connectedto housing 210 or in a bipolar configuration when the current source isconnected to a pair of functional elements 260). Alternatively,controller 250 can comprise one or more current sources that areattached to a matrix of switches that selectively connect the one ormore current sources to multiple functional elements 260 (e.g., connecta single current source to 2, 4, 8, 12 or 16 electrodes). In someembodiments, controller 250 is configured such that a stimulationwaveform signal provided to the current source passes through acapacitor (e.g., capacitor C1 shown), the capacitor providing DCbalance.

In some embodiments, implantable device 200 delivers a stimulationwaveform comprising delivery of multiple trains of pulses that aredelivered intermittently, a “burst stimulation” waveform as definedhereabove. For example, implantable device 200 can be configured todeliver a series or train of five pulses, each with a 1 msec pulsewidth. The each of the five pulses can be separated by an inter-pulsegap of 4 msec, creating a train-on period of 16 msec. These five pulsescan be repeated every 25 msec (the “inter-train period”). In someembodiments, implantable device 200 can be configured to deliver a burststimulation waveform comprising a pulse width between 5 μsec and 1 msec.Implantable device 200 can deliver a train or burst stimulation waveformcomprising pulses with constant pulse widths and/or varying pulsewidths, such as when the pulse widths (and/or other stimulationparameters) are varied randomly and/or systematically. Implantabledevice 200 can deliver a train or burst stimulation waveform with avaried or constant pulse shape selected from the group consisting of:sinusoid; square, rectangle; triangle (symmetric or asymmetric);trapezoid; sawtooth; ramp (e.g., a linear ramp); exponential curve;piece-wise step function; and combinations of one or more of these.Implantable device 200 can deliver a train or burst stimulation waveformwith an inter-pulse gap less than inter-train period (e.g., as shown inFIG. 30A). The inter-pulse gap can be relatively constant or it can bevaried, such as when implantable device 200 randomly varies theinter-pulse gap or varies the inter-pulse gap systematically. In someembodiments, the inter-pulse gap between any two pulses within a pulsetrain (or burst) can be varied between 0.1 μsec and the inter-trainperiod (or inter-burst period). Implantable device 200 can deliver atrain stimulation waveform with an inter-pulse gap between 1 μsec and 1second. Implantable device 200 can deliver a burst stimulation waveformwith an inter-train period between 1 μsec and 1 second. Implantabledevice 200 can deliver a burst stimulation waveform with an inter-burstperiod between 20 μsec and 24 hours. The inter-burst period can berelatively constant or it can be varied, such as when implantable device200 randomly varies the inter-burst period or varies the inter-burstperiod systematically. In some embodiments, inter-burst period is variedby the user, such as via a user using controller 550. In theseembodiments, user activation can be regulated with one or moresafeguards or other limits such as those incorporated into patientcontrolled analgesia devices. The inter-train period can be variedbetween 1 μsec and 24 hours. Implantable device 200 can deliver a trainor burst stimulation waveform with a train-on period (the time betweenthe onset of a first pulse in a pulse train to the end of the last pulsein a pulse train) between 10 μsec and 24 hours. The train-on and/orburst-on period can be relatively constant or it can be varied, such aswhen implantable device 200 randomly varies the train-on and/or burst-onperiod or varies the train-on and/or burst-on period systematically.Implantable device 200 can deliver a train or burst stimulation waveformwith a train or burst envelope selected from the group consisting of:cosine; cosine-squared; sine; square; rectangle; triangle (symmetric orasymmetric); trapezoid: sawtooth; ramp (e.g., linear ramp); andcombinations of one or more of these. Implantable device 200 can delivera train and/or burst stimulation waveform with a train ramp duration orburst ramp duration between 1 μsec to 10 minutes. Implantable device 200can deliver a train and/or burst stimulation waveform with a depth ofmodulation between train and/or bursts of between 1% and 99%. Forexample, between some or all of the trains and/or bursts (burst-off ortrain-off periods), a signal may be present and may contain the same ordifferent elements contained in the train-on and/or burst-on period.These burst-off or train-off periods may comprise a quiescent period asdescribed herein. The amplitude of the signal contained in thesequiescent period may be from 0% to 99% of the signal amplitude duringthe train-on and/or burst-on period, such as a signal with an amplitudeless than 50% of the signal amplitude during the train-on and/orburst-on period or another amplitude below a neuronal excitationthreshold.

In some embodiments, apparatus 10 is configured to deliver stimulationenergy to dorsal root ganglion and/or spinal cord tissue to treat acondition such as pain. In these and other embodiments, apparatus 10 canbe configured to provide a stimulation waveform comprising: acombination of low frequency stimulation (e.g., electrical energycomprising a low frequency signal) and burst stimulation; burststimulation (e.g., burst stimulation alone); a combination of lowfrequency stimulation and high frequency stimulation; a combination oflow frequency stimulation, high frequency stimulation and burststimulation; and combinations of one or more of these. The stimulationenergy provided by apparatus 10 can be delivered to tissue via one ormore functional elements 260, such as two or more electrodes whichdeliver similar or dissimilar stimulation waveforms simultaneouslyand/or sequentially. Each of the stimulation waveforms can comprise oneor more pulses comprising an entire phase or at least a portion of aphase at a superthreshold level. Alternatively or additionally, each ofthe stimulation waveforms can comprise one or more pulses comprising anentire phase or at least a portion of a phase at a subthreshold level.

In some embodiments, apparatus 10 is configured to vary one or morestimulation parameters. The stimulation parameters can be varied tooptimize (e.g., balance the benefits of) therapeutic benefit, systemefficiency, stimulation efficiency, avoidance and/or reduction ofparesthesia, and/or reduction of charge.

Referring now to FIG. 1A, an antenna assembly comprising an antenna anda shield is illustrated consistent with the present inventive concepts.Antenna assembly 1040 comprises a transmitting/receiving antenna,antenna 1041, and at least one shielding element (e.g., anelectromagnetic shielding element), shield 1042. In some embodiments,antenna assembly 1040 is of similar construction and arrangement to oneor more of antenna assemblies 1040 described herebelow in reference toFIGS. 2A-2F. In some embodiments, one or more external antennas 540 havethe construction and arrangement of one or more antenna assemblies 1040described herein, such as to transmit power and/or data and/or toreceive power and/or data, also as described herein. Alternatively oradditionally, one or more implantable antennas 240 can have theconstruction and arrangement of one or more antenna assemblies 1040described herein.

Antenna 1041 can comprise one or more antennas selected from the groupconsisting of: patch antenna; slot antenna; array of antennas; a loopantenna (e.g., a concentric loop antenna); antenna loaded with reactiveelements; dipole antenna; quadrupole antenna; multi-pole antenna;polarizable antenna; selectable conductors that form an antenna; andcombinations of one or more of these. Antenna 1041 can comprise anantenna element 1045 which is the portion of antenna 1041 which sendsand/or receives the wireless transmissions. Antenna element 1045 cancomprise one, two or more elements selected from the group consistingof: a wire; a conductive element; a conductive trace (e.g., a trace on aprinted circuit board or other substrate); a first conductive trace onone side of a substrate and a second conductive trace on the oppositeside of a substrate; a first conductive trace on a first substrate, anda second conductive trace on a second substrate; and combinationsthereof. In some embodiments, antenna element 1045 comprises a firstconductive trace on one side of a substrate and a second conductivetrace on the opposite side of a substrate, where the first and secondtraces are connected by one or more vias passing through the substrate,such as a connection made by at least 10 vias, or at least 100 vias,such as is described herebelow in reference to FIGS. 4E-F. In someembodiments, each antenna element 1045 comprises a conductive trace withan impedance below 10 mOhm, or an impedance below 20 mOhm. In someembodiments, antenna 1041 comprises three or more traces positioned inmultiple layers of a printed circuit board, such as three or more tracesconnected with vias. Antenna 1041, spacer 1043, and shield 1042determine basic properties of the antenna assembly 1040, including theinductance of antenna 1041, the quality factor Q, the bandwidth of thewireless communication link, and the matching network connected toantenna 1041. The parameters of elements 1041, 1042, and 1043 can beoptimized for the desired performance of system 10. For example, aconfiguration with reduced inductance increases the required capacitancein the matching network, which reduces the sensitivity of the matchingnetwork to small variations in capacitance.

Shield 1042 can be positioned on one side of antenna 1041, while adifferent, second side of antenna 1041 faces toward an area to whichantenna 1041 receives power and/or data and/or transmits power and/ordata. Shield 1042 can be configured to reduce losses or loading effectscaused by neighboring metallic and/or electrically conductive components(e.g., components of the same device or another device that can causeundesired loading, undesired coupling, and/or parasitic effects,“interfering components” herein). Shield 1042 can be configured toenhance the performance of one or more antennas 1041. Shield 1042 can beconfigured to allow miniaturization of one or more apparatus 10components (e.g., one or more components of an external device 500 orimplantable device 200 into which shield 1042 is positioned), such as bydesensitizing the miniaturized components to environmental disturbances(e.g., electromagnetic radiation) while preventing or at least reducingdegradation in system performance. In some embodiments, shield 1042 isconfigured to improve system performance, such as by providing magneticfield magnification to one or more antennas 1041. Shield 1042 can beconfigured to shield one or more components of apparatus 10 and/or otherelectronic components in the environment surrounding the one or moretransmitting antennas 1041 (e.g., at least a portion of the surroundingenvironment, such as to shield one or more electronic components on theside of shield 1042 opposite antenna 1041) from undesired radiationsfrom one or more antennas 1041, which can reduce electromagneticshielding or filtering requirements of the remainder of apparatus 10.

Shield 1042 can comprise ferrite (e.g., high-frequency ferrite) or othermaterial with a property selected from the group consisting of: highmagnetic permeability (u′) at the operating frequency of the antenna1041 transmission (e.g., a high frequency, such as a frequency above 1MHz, or above 10 MHz); low magnetic loss tangent (u″/u′) at theoperating frequency of the antenna 1041 transmission (e.g., a highfrequency, such as a frequency above 1 MHz, or above 10 MHz); lowconductivity at the operating frequency of the antenna 1041 transmission(e.g., a high frequency, such as a frequency above 1 MHz, or above 10MHz); and combinations of one or more of these. In some embodiments,transmissions from antenna 1041 are performed at an operating frequencybetween 1 MHz and 100 MHz, between 1 MHz and 50 MHz, or between 10 MHzand 50 MHz. In some embodiments, transmissions from antenna 1041 areperformed at an operating frequency of between 38.5 Mhz and 42.5 Mhz,such as at an operating frequency of approximately 40.5 Mhz or 40.68Mhz, or an operating frequency between 40.66 MHz and 40.7 MHz. In someembodiments, shield 1042 comprises a magnetic permeability (u′) ofgreater than or equal to 40. In some embodiments, shield 1042 comprisesa magnetic loss tangent (u″/u′) less than or equal to 0.025 (e.g., u″ isless than 1 when u′ is equal to 40). In some embodiments, shield 1042comprises a conductivity less than or equal to 1e−3 S/m, or less than orequal to 1e−5 S/m.

In some embodiments, shield 1042 comprises a thickness between 0.1 mmand 5 mm, such as a thickness between 0.5 mm and 2 mm. Shield 1042 cancomprise a coating or other layer of material, layer 1044, positioned onthe side of the shielding layer opposite the side facing antenna 1041,to increase shielding of unwanted radiation. Layer 1044 can comprise oneor more electromagnetic energy absorbing material (e.g., radiofrequencyenergy absorbing material), and/or conductive material. In someembodiments, shield 1042 comprises one or more holes or slots (e.g., toreduce weight of shield 1042), such as holes 1048 described herebelow inreference to FIG. 5A. The holes 1048 can be spaced in a way to minimizereduction in performance of shield 1042, such as at a spacing that issmaller than a wavelength of one or more electromagnetic signalsintended to be shielded by shield 1042. In some embodiments, holes,slots and/or other recesses or openings (“holes” herein) can be used toalign and/or position antenna 1041, spacer 1043, shield 1042 and/oranother component of antenna assembly 1040. In some embodiments, holescan be used to allow passage of a mechanical or electrical element(e.g., to allow an electrical connection to pass through shield 1042).

Shield 1042 can comprise a relatively flat geometry (e.g., a disk orplate that resides in essentially a single plane), or a multi-planargeometry, examples of each of which are described herebelow in referenceto FIGS. 2A-F. Shield 1042 can comprise a projecting portion, such as aprojecting portion that extends into a recess or opening of antenna1041, such as is shown in FIGS. 2D and 2E.

Shield 1042 can be configured to increase directivity of one or moreantennas 1041 and/or to focus the electromagnetic transmissions of oneor more antennas 1041, such as by limiting the directions to whichantenna 1041 transmits.

In some embodiments, the periphery of shield 1042 fully covers, and canextend beyond the periphery of antenna 1041. In some embodiments, theperiphery of shield 1042 covers a majority of the surface area (asdefined by the periphery) of antenna 1041, such as to shield at least50%, at least 70% or at least 80% of the surface area of antenna 1041.

In some embodiments, antenna assembly 1040 further includes an optionalspace-providing element, spacer 1043, which can comprise one or morespacers positioned between antenna 1041 and shield 1042, between antenna1041 and another component of system 10, and/or between shield 1042 andanother component of system 10.

Spacer 1043 may comprise a simple gap (e.g., a gap occupied by air orother gas), or a solid or liquid material. Spacer 1043 may comprise athickness (e.g., a spacing) of between 0.01 mm and 5 mm, between 0.25 mmand 1 mm, or approximately 0.8 mm. Spacer 1043 can comprise anadjustable spacer, such as when spacer 1043 comprises a compressiblematerial. Adjustment of the spacing via spacer 1043 can be used to tunethe antenna assembly 1040 performance. Spacer 1043 can be constructed ofnon-conductive dielectric materials, or other materials configured tominimize adverse impact on antenna 1041 performance. Spacer 1043 cancomprise a printed circuit board or other substrate, or a substrate ofthe present inventive concepts (e.g., substrate 211 or 511) can comprisespacer 1043. In some embodiments, spacer 1043 comprises a low dielectricloss tangent, such as a dielectric loss tangent less than or equal to0.05, such as less than or equal to 0.02 or less than or equal to 0.005.In some embodiments, spacer 1043 comprises glass-reinforced epoxylaminate (e.g., FR-4) and/or acetal (e.g., Delrin® material provided byDupont). Spacer 1043 can comprise one or more spacers, and each spacercan comprise one or more materials. In some embodiments, a first spacer1043 (e.g., a spacer comprising a first material) is positioned aboveantenna 1041, and a second spacer 1043 (e.g., a spacer comprising asecond, different material) is positioned below antenna 1041.

Antenna assembly 1040 can comprise one or more antennas 1041, such as anassembly 1040 comprising one or more antennas 1041, one or more shields1042, and an optional one or more spacers 1043. Multiple antennaassemblies 1040 and/or multiple antennas 1041 (e.g., in a single antennaassembly 1040) can be configured as independent antennas or as an arrayof electrically connected antennas (e.g., capacitively connectedantennas), such as is described herebelow in reference to FIG. 7.Multiple antennas assemblies 1040 and/or multiple antennas 1041 can beconfigured as a multi-directional antenna array (e.g., a 2-directionalor 3-directional array).

Referring now to FIGS. 2A-2F, views of various configurations of antennaassemblies are illustrated, consistent with the present inventiveconcepts. The antenna assemblies 1040 of FIGS. 2A-2F can be of similarconstruction and arrangement to antenna assembly 1040 describedhereabove in reference to FIG. 1A. Each of the antennas 1041 of FIGS.2A-2E are shown with a circular shaped periphery, and antenna 1041 ofFIG. 2F is shown with a rectangular shaped periphery. In should beunderstood that each antenna 1041 can comprise a circular or anon-circular periphery, such as a rectangular, trapezoidal or othernon-circular shape. Each of the antennas 1041 can comprise an opening(e.g., as shown in FIGS. 2A, 2D and 2E), which can comprise a circularshaped opening or a non-circular shaped opening (e.g., a rectangular,trapezoidal or other non-circular shaped opening). Each of the shields1042 of FIGS. 2A-2E are shown with a circular shaped periphery, andshield 1042 of FIG. 2F is shown with a rectangular shaped periphery. Itshould be understood that each shield 1042 can comprise a circular or anon-circular shaped periphery, such as a rectangular, trapezoidal orother non-circular shape. Each of the shields 1042 can comprise a shapeof its periphery (or at least the periphery of an extension or otherportion of shield 1042) that relatively matches the shape of an openingof antenna 1041 into which at least a portion of shield 1042 can bepositioned (e.g., a circular shaped shield 1042 positioned in a circularshaped opening of antenna 1041 as shown in FIGS. 2A, 2D and 2E). Each ofthe antenna assemblies 1040 can comprise a spacer, such as a spacerpositioned between antenna 1041 and shield 1042, such as spacer 1043described herein.

In FIG. 2A, side sectional and top views of an antenna assembly 1040 areshown, including an antenna 1041 with an open inner portion, and ashield 1042 positioned (e.g., fully positioned) in the open innerportion of antenna 1041.

In FIG. 2B, side and top views of an antenna assembly 1040 are shown, inwhich antenna 1041 and shield 1042 are positioned in a side-by-sidearrangement, such as when one side of antenna 1041 contacts one side ofshield 1042 (i.e., minimal or no gap is present). In some embodiments,the periphery of shield 1042 fully covers, and can extend beyond (asshown in FIG. 2B) the periphery of antenna 1041. In some embodiments,the periphery of shield 1042 covers a majority of the surface area (asdefined by the periphery) of antenna 1041, such as to shield at least50%, at least 70% or at least 80% of the surface area of antenna 1041.

In FIG. 2C, side and top views of an antenna assembly 1040 are shown, inwhich antenna 1041 and shield 1042 are positioned in a side-by-sidearrangement with a gap between the two components. In some embodiments,one or more spacing elements, spacer 1043 is positioned between antenna1041 and shield 1042. In some embodiments, spacer 1043 comprises air orother gas that is positioned between antenna 1041 and shield 1042 (e.g.,when antenna 1041 and shield 1042 are fixed or otherwise maintained withthe separation between the two, via one or more fixation elements notshown). In some embodiments, the periphery of shield 1042 fully covers,and can extend beyond (as shown in FIG. 2C) the periphery of antenna1041.

In FIG. 2D, side sectional and top views of an antenna assembly 1040 areshown, in which shield 1042 includes an extending portion 1042 a whichis positioned within an opening of antenna 1041. In some embodiments,the periphery of the top portion of shield 1042 fully covers, and canextend beyond (as shown in FIG. 2D) the periphery of antenna 1041.

In FIG. 2E, side sectional and top views of an antenna assembly 1040 areshown in which shield 1042 comprises an “H” shape that essentiallycovers a top and bottom surface of antenna 1041, as well as extendsthrough an opening of antenna 1041. In some embodiments, the peripheryof the top surface of shield 1042 and/or the periphery of the bottomsurface of shield 1042 fully covers the periphery of the associated topand bottom surfaces of antenna 1041, and can extend beyond the peripheryof those surfaces (as shown in FIG. 2E).

In FIG. 2F, side sectional and top views of an antenna assembly 1040 areshown in which shield 1042 comprise a flange portion 1042 b whichextends around at least a portion of the periphery of antenna 1041.

Referring now to FIG. 3, a schematic anatomical view of a medicalapparatus comprising an external system including a shielded antennaassembly is illustrated, consistent with the present inventive concepts.Apparatus 10 comprises at least one implantable device 200, and anexternal control device such as external device 500. Apparatus 10,implantable device 200, and/or external device 500 can be of similarconstruction and arrangement to similar components of apparatus 10described hereabove in reference to FIG. 1. Implantable device 200 cancomprise an implantable battery, capacitor or other power source (e.g.,energy storage assembly 270 shown and described hereabove in referenceto FIG. 1), such as a power source configured to provide stimulationenergy that is delivered by one or more functional elements 260 of lead265 (e.g., one or more electrode-based or other stimulation deliveringfunctional elements 260). In the embodiment shown in FIG. 3, implantabledevice 200 includes four functional elements 260 a-d, however more orfewer functional elements 260 can be included (e.g., 1-32 functionalelements configured to deliver electrical or other stimulation energy).

Implantable device 200 and energy storage assembly 270 can be configuredto deliver stimulation energy for a prolonged period of time (e.g., atleast 1 hour, at least 1 day, at least 1 month or at least 1 year),without receiving a wired or wireless power transmission from anothersource (e.g., the wireless power transmission described hereabove froman external device such as external device 500) during that time period.In some embodiments, energy storage assembly 270 can comprise a batteryor capacitor configured to provide (e.g., store) at least 1 mWh ofenergy, or at least 1 Wh of energy. In some embodiments, energy storageassembly 270 is configured to provide less than 1 mWh of energy (e.g.,to provide short term power in embodiments where implantable device 200receives wired or wireless power from a separate device). In someembodiments, implantable device 200 is configured to deliver one or morestimulation waveforms comprising a waveform shape as described hereabovein reference to FIG. 1, or as described in applicant's U.S. ProvisionalPatent Application Ser. No. 62/417,907, titled “Apparatus with EnhancedStimulation Waveforms”, filed Nov. 4, 2016. In some embodiments, theimplantable device 200 of FIG. 3 is configured to deliver one or morestimulation waveforms in which one or more stimulation parameters arevaried, such as via a random variation. In some embodiments, externaldevice 500 wirelessly transmits data (e.g., programming commands)through the patient's skin, to one or more implantable devices 200 thathave been implanted. In some embodiments, external device 500 wirelesslytransmits power (e.g., via an RF signal or inductive coupling) throughthe patient's skin to one or more implantable devices 200 that have beenimplanted, such as a power transfer that occurs at intervals of at least1 day, 1 week, 1 month or 1 year. Alternatively, external device 500transmits power to one or more implantable devices 200 relativelycontinuously, as described hereabove in reference to FIG. 1.

External device 500 comprises housing 510 which surrounds multiplecomponents and/or assemblies of external device 500, such as powersupply 570 (e.g., including one or more batteries, capacitors or otherenergy storage components) and substrate 511. One or more electroniccomponents 516 can be attached to substrate 511, and similarlyelectrically connected via one or more conductive traces of substrate511 (e.g., when substrate 511 comprises one or more single or multiplelayer printed circuit boards). Power supply 570 can be positioned (e.g.,attached) on a top surface of substrate 511 as shown, and can beelectrically connected to one or more conductive traces of substrate511. In some embodiments, power supply 570 can at least partially extendinto substrate 511 (e.g., extend into a recess or hole of substrate511). In some embodiments, power supply 570 comprises a user-replaceablebattery. Alternatively, power supply 570 can comprise a rechargeablepower source (e.g., a rechargeable battery). In these embodiments, powersupply 570 can be configured to be wirelessly recharged (e.g., viainductive charging and/or wireless power received by one or moreantennas 1041 of external device 500).

External device 500 further comprises an antenna 540, which can comprisean antenna assembly 1040 as described herein. Antenna assembly 1040shown in FIG. 3 includes a shield 1042 positioned on a bottom surface ofsubstrate 511, a spacer 1043 positioned on a bottom surface of shield1042, and an antenna 1041 positioned on a bottom surface of spacer 1043.Antenna 1041 comprises one or more antenna elements 1045, not shown butsuch as is described herein. Antenna 1041 is electrically connected tosubstrate 511 via an electrical connector, connector 517 (e.g., aflexible conduit as shown). Connector 517 can comprise one or moreconnecting components, such as: a cable; a ribbon cable; a flex circuit;a side-connector (e.g., a connector that electrically attaches to twocircuit boards); a compressible connector (e.g., a connector that ispositioned between two circuit boards); and combinations of one or moreof these. In some embodiments, antenna assembly 1040 is electricallyconnected to substrate 511 (e.g., to components 516 electricallyconnected to substrate 511) as described herebelow in reference to FIGS.4A-C.

In some embodiments, the periphery of shield 1042 fully covers, and canextend beyond (as shown in FIG. 3) the periphery of antenna 1041, suchas to provide shielding and/or improved antenna performance as describedherein. In the configuration and layout of antenna assembly 1040 shownin FIG. 3, shield 1042 is positioned such than antenna 1041 is shieldedfrom deleterious effects of components 516 and other electromagneticfield generating elements positioned above the top side of shield 1042,as described herein. Alternatively or additionally, this orientationimproves transmissions (e.g., power and/or data transmissions) ofantenna 1041 to implantable device 200, also as described herein.

Referring now to FIGS. 4A-C, an assembled, sectional, perspective view,an exploded perspective view, and an exploded side view of an externalsystem including a shielded antenna assembly are illustrated, consistentwith the present inventive concepts. External device 500 can be ofsimilar construction and arrangement and include similar components toexternal device 500 described hereabove in reference to FIG. 1. Externaldevice 500 comprises housing 510 which includes top portion 510 a andbottom portion 510 b. Top portion 510 a and bottom portion 510 b can befixedly attached to each other via one or more attachment elements suchas adhesive and/or via one or more attachment processes such as welding,such as to provide a sufficient seal to prevent a significant amount ofcontaminants from passing between the mating surfaces of top portion 510a and bottom portion 510 b. Housing 510, when assembled, surroundsmultiple components and/or assemblies of external device 500, such aspower supply 570 (e.g., including one or more batteries, capacitors orother energy storage components) and substrate 511. One or moreelectronic components 516 can be attached to substrate 511, andsimilarly electrically connected via one or more conductive traces ofsubstrate 511 (e.g., when substrate 511 comprises one or more single ormultiple layer printed circuit boards). Power supply 570 can bepositioned (e.g., attached) on a top surface of substrate 511 as shown,and can be electrically connected to one or more conductive traces ofsubstrate 511. Housing 510 can comprise a battery door, not shown, suchas to allow replacement of power supply 570.

External device 500 can comprise an assembly, strap assembly 592 whichcan include a flexible or rigid printed circuit, and can have a firstend and a second end that attach to substrate 511 and maintain theposition of power supply 570 relative to substrate 511. In someembodiments, strap assembly 592 and/or substrate 511 comprise one ormore switches (e.g., membrane or pushbutton electrical switches), suchas switches 593 a-c shown. Housing 510 can comprise one or more useraccessible buttons, buttons 512 a-c which are operably positioned tocorrespondingly activate switches 593 a-c, respectively, when buttons512 a-c are depressed. In some embodiments, external device 500 furthercomprises one or more covers surrounding (e.g., above) buttons 512 a-c,such as covers 513 a-c shown. Covers 513 a-c can comprise rigid and/orflexible covers, such as covers configured to prevent contaminants frompassing through housing 510 at buttons 512 a-c.

External device 500 comprises an external antenna 540 comprising antennaassembly 1040 including antenna 1041 and shield 1042. Antenna assembly1040 can comprise a similar construction and arrangement to any antennaassembly 1040 described herein. Antenna assembly 1040 comprises antennaelement 1045, which comprises one or more antenna elements as describedherein. In some embodiments, the antenna assembly of FIGS. 4A-C furthercomprises a spacing element (e.g., positioned between antenna 1041 andshield 1042), not shown but such as spacing element 1043 describedherein. Shield 1042 is positioned between antenna 1041 and one or moreelectronic components of external device 500 (e.g., components 516). Inthe configuration and layout of antenna assembly 1040 shown in FIGS.4A-C, shield 1042 is positioned such than antenna 1041 is shielded fromdeleterious effects of components 516 and other electromagnetic fieldgenerating elements positioned above the top side of shield 1042, asdescribed herein. Alternatively or additionally, this orientationimproves transmissions (e.g., power and/or data transmissions) ofantenna 1041 to implantable device 200, also as described herein.

In some embodiments, antenna assembly 1040 comprises a laminate assemblycomprising multiple stacked substrates (e.g., one or more substratescomprising FR4), such as an assembly comprising one or more printedcircuit boards onto which one or more antennas 1041 and/or othercomponents are mounted and/or electrically connected. In someembodiments, one or more substrates, or portions of substrates, functionas spacer 1043 (not shown). In some embodiments, antenna 1041 comprisesmultiple conductors (e.g., multiple antenna elements 1045) positioned ondifferent layers of the laminate assembly (e.g., copper traces separatedby a dielectric layer), such as is described herebelow in reference toFIGS. 4D-E.

Antenna assembly 1040 can be electrically connected to substrate 511(e.g., electrically connected to one or more components 516 of substrate511) via an electrical connector, connector 517, a compressibleconnector positioned between substrate 511 and antenna 1041. Inalternative embodiments, connector 517 comprises a flexible cableoperably attached to antenna assembly 1040 and substrate 511 (e.g., asshown in FIG. 3) and/or a clip connector connected to the sides ofantenna 1041 and substrate 511. In some embodiments, antenna 1041comprises a projection, tab 1046 shown, such as a tab including aconnecting portion to mate with connector 517. In some embodiments,shield 1042 can comprise a cutout 1047, and connector 517 can passthrough cutout 1047.

In some embodiments, antenna assembly 1040 comprises electroniccomponentry 1051, such as one or more electronic components configuredas a matching network for antenna 1041. In these embodiments, shield1042 can comprise cutout 1047 shown, into which components 1051 canextend (e.g., to create clearance for components 1051 to allow shield1042 to be positioned closer to antenna 1041). Antenna assembly 1040 cancomprise a matching network that includes a tuning element, such as anadjustable capacitor. The tuning element can comprise a capacitor with aquality factor that is high, such as to minimize degradation ofperformance of antenna assembly 1040. Tuning of antenna assembly 1040can be performed using a manufacturing fixture (e.g., a tuning performedprior to final assembly of antenna assembly 1040).

Referring now to FIG. 4D, a side, schematic view of a laminate antennaassembly comprising multiple antenna elements on different layers of thelaminate is illustrated, consistent with the present inventive concepts.Antenna assembly 1040 comprises an antenna 1041 comprising at least twoantenna elements, 1045 a and 1045 b. Antenna assembly 1040 can be ofsimilar construction and arrangement to any antenna assembly describedherein. Antenna elements 1045 a and 1045 b are attached to the bottomand top side, respectively, of substrate 1054. In some embodiments,substrate 1054 comprises a thickness (D2 as shown) of approximately 100μm, and antenna elements 1045 a-b each comprise 2 ounce copper traces.The thickness D2 of substrate 1054 can be chosen to determine a desiredseparation distance between two antenna elements 1045. In someembodiments, antenna elements 1045 a and 1045 b comprise loop antennas,such as loop antennas with relatively similar dimensions that arepositioned relatively aligned with each other on substrate 1054, such asis described herebelow in reference to FIGS. 4E-F. Antenna assembly 1040can further comprise a solder mask layer, and/or an overlay layer,positioned below antenna 1045 a as shown in FIG. 4D. Antenna assembly1040 can further comprise spacer 1043, trace layer 1055, a solder masklayer, and/or an overlay layer, also as shown in FIG. 4D. Spacer 1043comprises thickness D1, which can comprise a thickness of approximately0.8 mm or other thickness such as a thickness described hereabove inreference to spacer 1043 of FIG. 1A. Trace layer 1055 can be positionedon spacer 1043 (e.g., when spacer 1043 comprises FR4 or other printedcircuit board material). Trace layer 1055 can be electrically connectedto the one or more antenna element 1045 via an electrical cable,connector and/or via (e.g., a via through spacer 1043). Trace layer 1055can comprise one or more conductive pads (conductive pads 1057 shown inFIG. 4E), such as to mate with an electrical connector, such asconnector 517 described herein. One or more components, not shown butsuch as components 1051 described herein, can be attached andelectrically connected to trace layer 1055, such as when the componentsare configured as a matching network for antenna 1041 (e.g.,collectively for antenna elements 1045).

In some embodiments, the laminate antenna assembly 1040, including twoantenna elements 1045 a-b as shown, comprises a thickness ofapproximately 0.8 mm, or a thickness of less than 1.2 mm, such as tominimize the size of the associated housing 510 or 210 surroundingantenna assembly 1040.

In some embodiments, antenna 1041 comprises multiple antenna elements1045 (e.g., element 1045 a-b shown) that are electrically attached viaone or more vias that pass through each substrate separating the antennaelements 1045 (e.g., substrate 1054 including vias 1056 as shown), suchas a connection including at least 10 vias, at least 50 vias, at least100 vias, at least 500 vias, or at least 1000 vias that pass througheach substrate. All or a majority of the vias (e.g., vias 1056) can belimited to placement in the loop portion of the associated antennaelements 1045. Addition of the multiple vias to connect antenna elements1041 on either side of a substrate reduces the series resistance of theantenna (e.g., an antenna loop), thereby reducing energy loss during use(e.g., to improve battery life and result in other apparatus 10efficiencies). This reduction in resistance is achieved by increasingthe volume of electrically parallel conductive material (vias) betweenthe antennas 1041 and/or by increasing the available surface area ofconnecting conductive material to increase skin-effect conduction.Similar results can be achieved by adding additional antenna elements1041 on additional layers of a laminate antenna assembly 1040 (e.g.,connected by multiple vias or otherwise connected as described herein).In some embodiments, multiple vias are added such that every 10 mOhm ofreduced resistance achieves a transmission link gain of approximately0.3 dB.

In some embodiments, antenna assembly 1040 comprises more than twoantenna elements 1045, each neighboring pair separated by at least onesubstrate (e.g., a dielectric layer). For example, antenna assembly 1040can comprise at least 3 layered antenna elements 1045, at least 4layered antenna elements 1045, at least 5 layered antenna elements 1045,or at least 6 layered antenna elements 1045. Each neighboring pair ofantenna elements 1045 can be connected by one or more vias 1056 betweenthem. Antenna assembly 1040 can comprise multiple (e.g., 2, 3, 4 ormore) layers of antenna elements 1045 such as to increase the collectivesurface area of the antenna and/or to lower its resistance (e.g., due toskin effect).

Referring now to FIGS. 4E-F, a bottom view and a top view, respectively,of a laminate antenna assembly comprising multiple antenna elements andmultiple connecting vias is illustrated, consistent with the presentinventive concepts. In FIG. 4F, top layers (e.g., layers above sectionA-A of FIG. 4D) have been removed to illustrate antenna element 1045 b.An antenna 1041 comprises a first antenna element 1045 a (e.g., a firstcopper or other conductive trace) positioned on a bottom side ofsubstrate 1054 and a second antenna element 1045 b (e.g., a secondcopper or other conductive trace) positioned on a top side of substrate1054. Antenna 1041 includes multiple vias 1056 (e.g., at least 10 vias,at least 50 vias, at least 100 vias, at least 500 vias, or at least 1000vias that pass through substrate 1054) that reside within the width ofthe ring-shaped traces of antenna elements 1045 a and 1045 b to connectthe two elements.

Antenna 1041 can further include conductive pad 1057, which includes oneor more conductive pads located above antenna element 1045 b (e.g.,positioned on the top side of spacer 1043) for attaching antenna 1041 toa different component of external device 500 or implantable device 200(e.g., for attaching to substrate 511 of external device 500 viaconnector 517). Antenna 1041 can further include components 1051 (e.g.,also positioned on the top side of spacer 1043) which can be configuredas a matching network for antenna 1041. In some embodiments, spacer 1043and/or another substrate or layer of antenna 1041 comprises vias, suchas to electrically connect trace layer 1055 to antenna elements 1045 aand/or 1045 b, and/or another electronic component of antenna 1041.

Referring now to FIGS. 5A-B, side sectional views of external devices,each including a shielded antenna assembly, are illustrated, consistentwith the present inventive concepts. External device 500's of FIGS. 5A-Bcan be of similar construction and arrangement and include similarcomponents to external device 500 described hereabove in reference toFIG. 1. Antenna assembly 1040 can be of similar construction andarrangement to any antenna assembly 1040 described herein. In someembodiments, antenna assembly 1040 includes multiple antennas 1041, suchas are shown in FIGS. 5A-B. In these embodiments, one or more antennas1041 can be configured to receive wireless power, such as to rechargepower supply 570 (e.g., when power supply 570 comprises a rechargeablebattery or capacitor).

In FIG. 5A, external device 500 comprises an antenna 540 comprising anantenna assembly 1040 including two antennas 1041, antennas 1041 a and1041 b shown, and two shields 1042, shield 1042 a and 1042 b shown.Antenna assembly 1040 can be of similar construction and arrangement toany antenna assembly 1040 described herein. Antenna 1041 a is positionedabove substrate 511, with shield 1042 a positioned between antenna 1041a and substrate 511. Antenna 1041 b is positioned below substrate 511,with shield 1042 b positioned between antenna 1041 b and substrate 511.In the configuration and layout of antenna assembly 1040 shown in FIG.5A, shield 1042 a is positioned such than antenna 1041 a is shieldedfrom deleterious effects of components 516 and other electromagneticfield generating elements positioned below shield 1042 a, and shield1042 b is positioned such that antenna 1041 b is shielded fromdeleterious effects of components 516 and other electromagnetic fieldgenerating elements positioned above shield 1042 b, each as describedherein. Alternatively or additionally, this orientation improvestransmissions (e.g., power and/or data transmissions) of antennas 1041 aand 1041 b to implantable device 200, also as described herein.

In FIG. 5B, external device 500 comprises an antenna 540 comprising anantenna assembly 1040 including three antennas 1041, antennas 1041 a,1041 b and 1041 c shown, and a shield 1042. Antenna 1041 a is positionedabove substrate 511, with a top portion of shield 1042 positionedbetween antenna 1041 a and substrate 511. Antenna 1041 b is positionedbelow substrate 511, with a bottom portion of shield 1042 positionedbetween antenna 1041 b and substrate 511. Antenna 1041 c is positionedto the left of substrate 511, with a side portion of shield 1042positioned between antenna 1041 c and substrate 511. In alternativeembodiments, one or more of the top portion, bottom portion and/or sideportion of shield 1042 comprises a separate discrete shield (e.g., afirst shield 1042 a positioned below antenna 1041 a, a second shield1042 b positioned above antenna 1041 b, and a third shield 1042 cpositioned to the right of antenna 1041 c). In some embodiments, one ormore spacers 1043 are included, such as spacers 1043 a-c shown in FIG.5B and positioned between antennas 1041 a-c, respectively, and shield1042. In the configuration and layout of antenna assembly 1040 shown inFIG. 5B, the top portion of shield 1042 is positioned such that antenna1041 a is shielded from deleterious effects of components 516 and otherelectromagnetic field generating elements positioned below the topportion of shield 1042, the bottom portion of shield 1042 is positionedsuch that antenna 1041 b is shielded from deleterious effects ofcomponents 516 and other electromagnetic field generating elementspositioned above the bottom portion of shield 1042, and the side portionof shield 1042 is positioned such that antenna 1041 c is shielded fromdeleterious effects of components 516 and other electromagnetic fieldgenerating elements positioned to the right of the side portion ofshield 1042, each shielding effect as described herein. Alternatively oradditionally, this configuration of shield 1042 (including the threeplanar portions as shown in FIG. 5B or three separate shields 1042positioned in the three planes) improves transmissions (e.g., powerand/or data transmissions) of antennas 1041 a, 1041 b and 1041 c toimplantable device 200, also as described herein.

In some embodiments, an antenna assembly 1040 includes a shield 1042with one or more holes or slots, holes 1048 shown in FIG. 5A, such as toreduce weight.

As described in reference to FIGS. 4 A-C and 5A, shield 1042 cancomprise multiple shields and/or shields that lie on multiple planesthat can be configured to shield one or more antennas 1041 from one ormore electromagnetic field generating components positioned in multipledirections relative to each antenna 1041.

While the embodiments shown in FIGS. 4A-C and 5A include one or moreshields included in an antenna assembly of an external device 500,similar antenna assemblies can be included in one or more implantabledevices 200.

Referring now to FIG. 6, a side sectional view of an implantable deviceincluding a shielded antenna assembly is illustrated, consistent withthe present inventive concepts. Implantable device 500 can be of similarconstruction and arrangement and include similar components toimplantable device 200 described hereabove in reference to FIG. 1.Implantable device 200 comprises lead 265 including one or morefunctional elements 260 configured to stimulate tissue (e.g., one ormore electrode-based or other stimulation energy delivering functionalelements 260). Implantable device 200 further comprises housing 210,which can include one or more attachable portions which can be fixedlyattached to each other via one or more attachment elements such asadhesive and/or via one or more attachment processes such as welding,such as to provide a sufficient seal to prevent a significant amount ofcontaminants from passing between the multiple housing 210 portions.Housing 210 surrounds multiple components and/or assemblies ofimplantable device 200, such as energy storage assembly 270 (e.g.,including one or more batteries, capacitors or other energy storagecomponents) and substrate 211. One or more electronic components 216 canbe attached to substrate 211, and similarly electrically connected viaone or more conductive traces of substrate 211 (e.g., when substrate 211comprises one or more single or multiple layer printed circuit boards).Energy storage assembly 270 can be positioned (e.g., attached) on a topsurface of substrate 211, or positioned at a separate location as shown,and can be electrically connected to one or more conductive traces ofsubstrate 211.

Implantable device 200 can comprise an antenna 240 comprising one ormore antennas, such as an antenna assembly 1040 comprising one, two,three, four or more antennas, such as the three antennas 1041 a-c shown.Antenna assembly 1040 can comprise one or more shields, such as arectangular cross section shield, shield 1042 shown. Each surface ofshield 1042 is configured to shield one of antennas 1041 a-c fromcomponents 216 positioned on substrate 211, as described herein.Alternatively or additionally, this configuration of shield 1042improves transmissions (e.g., power and/or data transmissions) ofantennas 1041 a-c, also as described herein. In some embodiments,implantable device 200 comprises a single antenna 1041, or two antennas1041, such as when implantable device 200 further comprises a singleshield 1042, two shields 1042, or three or more shields 1042, whichcollectively provide shielding and/or improved transmission of the oneor two antennas 1041.

Referring now to FIG. 7, a perspective view of an antenna assemblycomprising multiple antennas is illustrated, consistent with the presentinventive concepts. Antenna assembly 1040 of FIG. 7 can be included inexternal device 500 and/or implantable device 200 of system 10. Antennaassembly 1040 comprises two or more antennas 1041, such as the fourantennas 1041 a-d shown. Each antenna 1041 a-d can comprise areceiving/transmitting portion, antenna element 1045. Antenna assembly1040 can comprise one or more shields 1042, such as four shields 1042a-d which are positioned relatively concentrically about the fourantennas 1041 a-d, respectively. In an alternative embodiment, fewerthan four shields 1042 are included, such as a single shield positionedrelatively concentrically about the periphery defined collectively bythe four antennas 1041 a-d. In some embodiments, one or more of antennas1041 a-d comprises an antenna 1041 as described hereabove in referenceto FIG. 1A or otherwise as described herein.

In some embodiments, two or more of the antennas 1041 are electricallyconnected, such as via a conductor, conductor 1052 (conductors 1052 a-dshown connecting antennas 1041 a-d). In these embodiments, one or morecomponents 1053 (components 1053 a-d shown) can also be electricallyconnected with the conductor 1052 (e.g., in series with conductor 1052as shown). Each component 1053 can comprise one or more electricalcomponents, such as components which include one or more capacitors orother impedance elements. In some embodiments, the one or more impedanceelements can have their impedance dynamically adjusted, enabling phaseand amplitude control of each antenna 1041 independently, such as toprovide beam steering and/or power transfer optimization (e.g., to oneor more receiving antennas 240 of an implantable device 200 positionedrelatively proximate the array of antennas 1041). In some embodiments,component 1053 comprises one or more capacitors comprising silicon bulkcapacitors, deep well trench capacitors, and/or other variablecapacitors. Component 1053 can comprise one or more capacitors and biascontrol circuitry configured to modulate the impedance. In someembodiments, component 1053 comprises one or more high frequencytransmission gate switches which can be configured to modify theconnection scheme between antennas 1041 of the array, such as to adjustbeam formation and/or adjust (e.g., optimize) power transfer (e.g., toone or more antennas 240 of an implanted device 200). In someembodiments, component 1053 can comprise one or more componentsintegrated into a silicon wafer, such as to sense and control impedanceof component 1053. In some embodiments, component 1053 (or otherelectronic circuitry of system 10) can comprise components including amicrocontroller configured to measure and/or control impedance ofcomponent 1053 and/or other portions of antenna assembly 1040.

In some embodiments, antennas 1041 a-d are mounted to a substrate, notshown but such as a substrate in which conductors 1052 a-d are tracesthat are also mounted to the substrate and/or components 1053 a-d thatare also mounted to the substrate.

Referring now to FIG. 8, a perspective view of an external devicecomprising an attached antenna assembly is illustrated, consistent withthe present inventive concepts. External device 500 comprises a housing510 including two discrete portions, housing 510 a and housing 510 bshown. Housing 510 a surrounds at least transmitter 530 and power supply570, as described herein. Housing 510 b surrounds antenna assembly 1040,also as described herein. Antenna assembly 1040 includes antenna 1041which includes at least one antenna element 1045 (e.g., two or moreantenna elements 1045 as described hereabove in reference to FIGS.4D-F). Antenna assembly 1040 can further include at least one shieldingelement, shield 1042. Antenna assembly 1040 is electrically connected totransmitter 530 by connector 517 (e.g., a flexible or other connectingfilament comprising one or more wires or otherwise as described herein).In some embodiments, antenna assembly 1040 further comprises one or morespace-providing elements, not shown but such as spacer 1043 describedherein.

External device 500 of FIG. 8 can be configured such that housing 510 bis positioned on or at least proximate the patient's skin, such as totransfer power and/or data to a nearby implantable device 200 which hasbeen implanted under the patient's skin. In this use, housing 510 a canbe positioned relatively away from the patient's skin, such as at alocation on a belt or in a pocket of a patient-worn garment.

While the embodiments described hereabove have focused primarily onelectrical and other stimulation systems, all medical apparatusincluding an implantable device that receives power and/or data from anexternal device should be considered within the spirit and scope of thisapplication.

While the preferred embodiments of the devices and methods have beendescribed in reference to the environment in which they were developed,they are merely illustrative of the principles of the present inventiveconcepts. Modification or combinations of the above-describedassemblies, other embodiments, configurations, and methods for carryingout the invention, and variations of aspects of the invention that areobvious to those of skill in the art are intended to be within the scopeof the claims. In addition, where this application has listed the stepsof a method or procedure in a specific order, it may be possible, oreven expedient in certain circumstances, to change the order in whichsome steps are performed, and it is intended that the particular stepsof the method or procedure claim set forth herebelow not be construed asbeing order-specific unless such order specificity is expressly statedin the claim.

We claim:
 1. A medical apparatus for a patient, comprising: an externalsystem configured to transmit one or more transmission signals, eachtransmission signal comprising at least power or data; and animplantable system configured to receive the one or more transmissionsignals from the external system; wherein the external system comprisesa first external device comprising: an external antenna assemblyconfigured to transmit a first transmission signal to the implantablesystem, the first transmission signal comprising at least power or data;an external transmitter configured to drive the external antennaassembly; an external power supply configured to provide power to atleast the external transmitter; and an external controller configured tocontrol the external transmitter; and wherein the implantable systemcomprises a first implantable device comprising: an implantable antennaassembly configured to receive the first transmission signal from thefirst external device; an implantable receiver configured to receive thefirst transmission signal from the implantable antenna assembly; atleast one implantable functional element configured to interface withthe patient; an implantable controller configured to control the atleast one implantable functional element; an implantable energy storageassembly configured to provide power to an element selected from thegroup consisting of: the at least one implantable functional element;the implantable controller; the implantable receiver; and combinationsthereof; and an implantable housing surrounding at least the implantablecontroller and the implantable receiver; wherein the external antennaassembly comprises: at least one external antenna; and at least oneshielding element positioned between the at least one external antennaand at least one of the external power supply or the externalcontroller, such that the at least one external antenna is on a firstside of the at least one shielding element and the at least one of theexternal power supply or external controller is on a second side of theat least one shielding element opposite the first side; wherein the atleast one shielding element is configured to reduce losses and/orloading effects caused by deleterious effects of the at least oneexternal power supply or external controller; wherein the at least oneshielding element comprises one or more electromagnetic absorptivematerials and one or more conductive materials on the second side, andwherein the one or more electromagnetic absorptive materials and the oneor more conductive materials are configured to increase shielding of theat least one shielding element, wherein the at least one shieldingelement comprises a material having a low magnetic loss tangent (u″/u′)at the operating frequency of the antenna transmission, wherein themagnetic loss tangent (u″/u′) is less than or equal to 0.025 at theoperating frequency of the antenna transmission, and wherein the one ormore conductive materials have a conductivity of less than or equal to1e−3 S/m or 1e−5 S/m at the operating frequency.
 2. The medicalapparatus according to claim 1, wherein the at least one shieldingelement is configured to shield one or more of the external powersupply, the external controller, and the external transmitter fromundesired radiations from the external antenna.
 3. The medical apparatusaccording to claim 1, wherein the at least one shielding element isconfigured to magnify a magnetic field of the external antenna assembly.4. The medical apparatus according to claim 1, wherein the at least oneshielding element comprises a hole and wherein the first external devicecomprises an electrical connection that passes through the hole.
 5. Themedical apparatus according to claim 1, wherein the at least oneshielding element is configured to increase directivity of the externalantenna assembly.
 6. The medical apparatus according to claim 1, whereinthe at least one shielding element is configured to limit a transmittingdirection of the external antenna assembly.
 7. The medical apparatusaccording to claim 1, wherein the first external device furthercomprises a spacer positioned between the at least one external antennaand the at least one shielding element.
 8. The medical apparatusaccording to claim 7, wherein the spacer comprises a printed circuitboard.
 9. The medical apparatus according to claim 8, wherein the spacercomprises a thickness between 0.01 mm and 5 mm.
 10. The medicalapparatus according to claim 8, wherein the spacer comprises anon-conductive dielectric material.
 11. The medical apparatus accordingto claim 1, wherein a periphery of the at least one shielding elementfully covers a periphery of the at least one external antenna.
 12. Themedical apparatus according to claim 11, wherein the periphery of the atleast one shielding element extends beyond the periphery of the at leastone external antenna.
 13. The medical apparatus according to claim 1,wherein the first external device comprises electronic componentryconfigured as a matching network.
 14. The medical apparatus according toclaim 13, wherein the at least one shielding element comprises a cutoutand the electronic componentry extends into the cutout.
 15. The medicalapparatus according to claim 13, wherein the electronic componentryincludes a tuning element.
 16. The medical apparatus according to claim1, wherein the at least one external antenna is configured to delivertransmissions with an operating frequency above 1 Mhz.
 17. The medicalapparatus according to claim 1, wherein the at least one externalantenna is configured to deliver transmissions with an operatingfrequency above 10 MHz.
 18. The medical apparatus according to claim 1,wherein the at least one shielding element comprises high frequencyferrite.
 19. The medical apparatus according to claim 1, wherein the atleast one shielding element comprises a material selected from the groupconsisting of: electromagnetically absorptive material; RF absorptivematerial; conductive material; and combinations thereof.
 20. The medicalapparatus according to claim 1, wherein the at least one shieldingelement is configured to shield one or more electronic componentssurrounding the at least one external antenna.
 21. The medical apparatusaccording to claim 1, wherein the external device further comprises ahousing, wherein the at least one shielding element, the externalantenna, the external power supply, and the external controller arepositioned within the housing of the external device.
 22. The medicalapparatus according to claim 1, wherein both the external power supplyand the external controller are on the second side of the at least oneshielding element.